Written for the prompt on st_xi_kink: Spock gets turned into a baby. He likes his binky.

"You can fix him, right, Bones?" Jim asked, looking hopeful.

"Fix him! Jim, I don't even know what they've done to him," Bones shook his head helplessly.

"Your conclusion, Captain," Spock spoke up with a scowl, "That there is anything wrong with me is incorrect. I assure you that I am well and do not require a doctor."

Jim stared. Bones stared.

"Spock… You're three."

"Affirmative. I am three years, two months, and thirteen days old, according to Earth standards."

Jim shook his head, "Bones. Bones, you have to fix him. He's creeping me out. He's not even, he's… He's being all logical and he's three."

"I don't know how," Bones snapped, "I'm a doctor, not a miracle worker."

Jim rolled his eyes, "Well, what am I supposed to do with him until you can… figure it out?"

"You aren't leaving him here!"

"If you would please return me to my mother," Spock was scowling even more. At least, Jim thought wildly, he looked like a normal kid. Apparently, Vulcans picked up precise grammar very early on, but that emotionless mask they had going wasn't something they learned until later.

"Um," Jim thought frantically, "You're on a starship, Spock. We'll take you to your mother as soon as we can."

"Jim," Bones hissed.

"Shh," Jim hissed back. "He doesn't need to know. He's three."

Bones sighed, "Fine. See if Uhura wants to deal with him."

Spock kicked his feet, "Captain."

"One minute, Spock. Uhura? Bones, Uhura would kick my ass and give me a lecture on gender stereotypes if I ask her!"

"Captain," Spock all but shouted. The captain and physician turned to him in shock. "I would like my binky, please."

"Binky?" Jim repeated, blinking owlishly. "As in pacifier?"

"Correct."

"You… have a binky?"

"Yes," the tiny Vulcan was clearly becoming annoyed, "And I would very much like to have it now."

"Um. Your mother didn't, ah, pack yours along, I'm afraid."

"You are lying to me. My mother would not fail to pack my binky."

"Um, well."

"I," Spock's voice was rising at quite an alarming rate, "Want my binky!"

"Okay! Okay, okay! I'll find it, okay, just… don't scream. Holy shit, Bones, he's, he's crying."

It was true. Large, fat tears were beginning to roll down Spock's cheeks. Jim stared in horror as the commander-turned-toddler threw his head back and wailed as if he were in pain.

Jim took off, wondering where in the hell he was going to find a pacifier, of all things, for his first officer.