A/N: Sorry this is late. Just too much to do on Halloween. But it is still Halloween in California. This would be in my Back Porch universe.

Mission: Costumes

For once it wasn't Clint Barton in the hospital. Laura felt such a sharp pain shoot through her body that she thought she was having a heart attack. After a frantic drive to the hospital, Clint got good news and bad news. It wasn't a heart attack, but Laura needed gallbladder surgery right now.

On the day before Halloween.

The sight of grinning pumpkin decorations reminded Laura's frantic husband of his fatherly duties. The baby had been left with a helpful neighbor, but his two oldest children were due to get out of school in three hours.

Even worse, the kids didn't have any Halloween costumes yet.

Clint needed to stay at the hospital to fill out interminable forms while they did tests on his wife. Hawkeye needed backup, so he called in the Avengers.

His partner Natasha Romanoff literally flew to the rescue, commandeering a Stark jet and the Avengers leader. She brought Steve Rogers with her because she might need his artistic talents — and because he already had a costume.

Clint had called the school to tell them to expect Natasha. When the bell rang, the assistant principal met Lila at her classroom door while Cooper's teacher told him to go to directly to the office to meet his sister.

Cooper wondered if they'd found out who put the lizard in the girl's restroom. It had been a dud prank since most of the girls thought the lizard was cute; but he might still get in trouble for it. But when he saw the red-haired woman in jeans, boots and a puffy, bright pink down jacket, Cooper knew he wasn't the one in trouble.

His mouth went dry, but Natasha forestalled his fears. "Everyone's fine. Well, you're mother needs to have a little operation. She should be home on Monday. So your father called me to take care of you this weekend, while he stays with your mother in Pinehurst."

Cooper understood that. The school was in one town and the hospital in another on the opposite side of the farm.

"Auntie Nat!" Lila cried joyfully, running to greet her favorite honorary aunt. "Why are you here? Did something happen to Daddy?"

She didn't sound as scared as her brother felt, but she was younger and had confidence her father could overcome anything. She was more worried when Natasha explained about her mother.

"And she's going to be OK?" Lila asked anxiously. She was used to her father needing to go to the hospital, not her mother.

"She's going to be fine, baby," Natasha said gently. "They're going to take out her gallbladder. Then the pain will go away. She expects to be home Monday. I talked to your father and he seemed more worried about you two not having Halloween costumes, than about your mother being OK. That tells me she'll be just fine."

Cooper and Lila knew that was true. Natasha saw them both relax. "What are we going to do for costumes, Auntie Nat?" Lila asked. "Mommy was going to make them, but she didn't feel well. Is that why she needs an operation?" the girl realized.

"That's why," Natasha agreed.

"I guess we can just buy costumes," Cooper offered, though it had been a point of honor in the Barton household to make their own. "I don't think we can wear last year's. We've both been growing," he said proudly.

"Not to worry," Natasha said. "I brought someone who's an expert at costumes."

As if on cue, Steve stuck his head through the door. "Are we almost ready to go?" he complained. "People are beginning to stare at the strange man standing around the school parking lot."

With his dark-rimmed glasses, slouched posture and baseball cap pulled low over his eyes, he did look more like a suspicious character than trustworthy Captain America.

"Uncle Steve!" Lila said in delight. "Are you going to help us make costumes?"

She flew at the man and he swept her up easily, holding her at arm's length above his head while she giggled. "That's our mission," Steve agreed.

On the way back to the Barton farm, they stopped to pick up baby Nathaniel from motherly Mrs. Robeson, the apple farmer's wife. She was sympathetic to Laura's plight and pressed a jar of applesauce and a casserole from her freezer on "Natalie," so they wouldn't have to worry about cooking.

Natasha tried to refuse, but Cooper quickly took the dish out of the woman's hands, while Lila collected the applesauce. "Thank you, Mrs. Robeson," Cooper said politely.

"You're welcome, Cooper," she said. "When your mother gets home, tell her she's not to strain herself. She can call me for anything."

"Thank you, ma'am," Steve said sincerely, and got a dimpled smile in return for his politeness.

As they went back to the rented car, Natasha said crossly. "You didn't have to take the poor woman's food. I can cook, you know."

"Of course you can, Auntie Nat," Lila said loyally, though not as if she believed it. (Natasha could cook, but the kids had inflated standards, because Laura was just that good.)

"Mrs. Robeson is the best cook in two counties," Cooper confided to Steve. "She has to bring two dishes to the church potlucks because everyone eats up hers first. I saw two boys get into a fistfight over the last serving of her taco casserole once."

"And your junior Hawkeye eyes saw that was the label on the foil cover," said Steve, who had pretty sharp eyes himself.

"Ex-actly!"

The taco casserole was yummy. They let Steve have half and split the rest among themselves, while Nathaniel gummed Laura's homemade chicken puree and some of the Robeson's prize-winning applesauce.

Clint called just as they finished dinner. He sounded exhausted. Apparently "must have an operation right now" was doctor speak for "must begin tests to have an operation tomorrow morning." He'd had a very long day full of emotional exhaustion.

Laura had undergone blood tests and an ultrasound, as well as an EKG because of a history of heart disease in her family. She was now ready to have surgery at 10 a.m.

She was also more than ready to talk to her kids.

She sounded a little groggy from her pain medicine, but reassured Cooper and Lila that she was going to be fine. "They only have to make three little holes to get the gallbladder out. I won't even be able to compare scars with your father."

Clint wondered if he should come home, but Natasha ordered him to stay with Laura and get some sleep. "We'll be fine. Tomorrow we'll make costumes and go trick-or-treating. It'll be fun."

Steve rolled his eyes, because he remembered Natasha's idea of fun. Clint did, too.

"Don't have too much fun with my kids," he warned.

"Worrywart," Natasha said, and hung up.

After Natasha and Steve diligently cleaning up the kitchen, Nathaniel played with wooden blocks while the other four planned their costumes.

The first snag was that Lila and Cooper wanted to be the same character. They argued fiercely, until Steve suggested another character. Cooper immediately called dibs. Lila was happy with her first choice. Cooper generously offered his black down vest for Lila's costume. It was perfect because it would make her look bigger and more muscular like her hero.

Peace was restored and the teammates scattered to collect the tools, fabric, pillow stuffing, cardboard and craft paint they would need for their Halloween projects. Steve also brought out his personal art supplies for detail work.

Then everyone went to bed, because they had a lot to do on Halloween before trick-or-treating that night.

"Does this costume make my butt look big?" Natasha queried, as she looked over her shoulder.

Steve eyed her critically. "Yes," he answered.

"Good," Natasha decided. She was going to wear her Black Widow outfit, but she didn't want to look like Natasha Romanoff. She wanted to look like Natalie Rushman wearing a Black Widow costume, so she padded her rear and thighs and planned to bind her breasts to make them look smaller. She did the same for Steve, making a pair of padded shorts he could wear over his uniform, so he looked less like a specimen and more like an ordinary Joe.

Natasha was used to adapting costumes on the fly. Sometimes you found out a mark was more attracted to an innocent convent girl than a voluptuous prostitute, so you had to change the dress you brought.

Steve painted her an oversized red hourglass logo she could fasten to her belt, to make her uniform look more "costumey." He made a big silver cardboard star for his chest and round cardboard shield for his back. Costume, not uniform!

Lila's costume was taken care of with a pair of black jeans, her brother's sleeveless vest and a Nerf toy. All she needed was to slick back her hair.

Cooper's costume took more work, but Steve was up to the challenge. Heck, he was excited to use his art skills. He cut out big triangles of cardboard, hinged them together and attached them to the straps of a backpack that was falling apart, so Cooper could wear them. Then he spray-painted the cardboard gunmetal gray and brush-painted a pair of swim goggles black. Cooper would wear a black T-shirt and black jeans, with Nerf guns to complete his look.

A suggestion from Steve made Natasha laugh out loud. She painted black hair dye (she always had hair dye in her kit) on the outside of an old hooded onesie for Nathaniel. A few black pipe cleaners finished the outfit. Nathaniel was fascinated by the way the pipe cleaners bounced around when he batted at them.

Clint had called around noon to say the surgery went well and Laura herself called later to reassure everyone, and tell her kids to have fun trick-or-treating. So when dark fell, the kids and Avengers were dressed and ready to go.

The main venue for trick-or-treating was the neighborhood around their school, but their first stop was the Robesons. Lila and Cooper were the only ones to visit that farmhouse; it was too far out of the way. But the older couple enjoyed seeing the Bartons' creative costumes.

As they approached the door, Cooper ran ahead, eager to show off his costume.

"Manners!" Steve protested, chasing after the boy, but Cooper had already rung the doorbell.

"Trick or treat!"

Mrs. Robeson exclaimed over the costume. "Oh look, dear. It's the Avengers!"

Steve's Captain America getup made that clear. Cooper's was a little more obscure, until he spread his cardboard wings by pulling a string.

"It's the flying guy. Falcon, isn't it?" Mr. Robeson said.

Cooper beamed and made his wings flap, as Mrs. Robeson dropped a full-sized candy bar into his bag. "Yes, Falcon," he agreed.

"I'd have thought you'd want to be that Hawkeye fella," Mr. Robeson said. "Your whole family likes archery." He expected to see Cooper and/or his sister in the Olympics some day.

"I couldn't be Hawkeye," Cooper said seriously. He spread his wings and said, "Up, up and away!" Cap obligingly lifted Cooper off the ground, flying him over the head of his sister and then set him back down.

"I couldn't be Hawkeye, because she's Hawkeye!" Cooper announced grandly.

Lila's hair was slicked back so her face looked boyish. Her arms were bare beneath the down vest. She carried a Nerf bow and wore a quiver with Nerf arrows

Mr. Robeson laughed appreciatively. "Well done!"

"Why not carry your real bow, dear?" Mrs. Robeson said, as she doled out a treat.

"Nerf bows are for fun. Real bows are for work," Lila said, obviously parroting her father.

The Robeson's nodded understanding.

"Natalie, you make a darling Black Widow," Mrs. Robeson said. Natasha gave a little curtsey in response. "And who's this little bug?" Mrs. Robeson continued.

Natasha held out Nathaniel, dressed in black with black antennas plus a few extra legs attached to his middle.

"This is one of the new heroes," Steve said solemnly, making his voice deeper as if he was trying to sound like Cap. (Which made him not sound like Cap.) "You may not have heard of him. This is Ant-Man."

The Robeson's laughed, thinking the group had made up a hero name for Nathaniel.

"Ant-Baby is more like it," Mrs. Robeson said, wrinkling her nose at Nathaniel who giggled at the familiar face.

She dropped two candy bars in the baby's bucket, winking at Natalie and Steve, who she expected to claim the candy. "Don't let him eat all the chocolate at once," she teased.

"No ma'am," Steve answered. "We'll make sure he shares."

Laughing, the Robesons shut the door and the Avengers started down the long driveway to their car.

"Up, up and away!" Cooper said hopefully.

Steve picked the boy up under one arm and "flew" him along the driveway as if the boy was a toddler. Lila walked contentedly beside Auntie Nat.

"Maybe Sam does need a battle cry," Natasha said, amused by Cooper's antics.

"Maybe. But I'm pretty sure 'up, up and away' is taken," Steve said dryly.