Disclaimer: I only own the plot, not the TMNT, but I wish I did.
Why Me?
"Fever's down that's good", Donatello says as he leaves Mikey's room.
"Donatello/Don why has he been so sick lately?" asks Leo, Raph, and Splinter together.
"I don't know, his hormones are strangely off, that maybe why, but I can't place exactly what's wrong with him."
"My sons we all should rest, and let Michelangelo sleep."
"Yes Sensei," they say.
One by one they enter the room to tell Mikey good night and gently kiss his head, they all loved him he was the baby, but not just that he was their baby. They all go to their rooms to sleep, and while they drift off Mikey begins to have a nightmare. He dreams that he is with his bros in a fight with The Foot, and they are being more overprotective than usual.
"Dudes what is up with you guys?" he asked.
"Wha' do ya mean?" asked Raph.
"You are way too protective today."
"We are always this protective when it comes to you sis", said Leo and Donnie.
"What I'm your baby bro…OMG", he sees his reflection it has blonde hair and a female figure with his recognizable baby blues.
Mikey wakes up chilly, panting, and shaking from it. He walks to the bathroom, gets a warm wet cloth, and starts wiping his face off. After about ten minutes he calms down. He goes to leave but something in the mirror catches his eye, he stops, looks in it, looks away, and looks in it again. He sees long, wavy blonde hair, a curvy figure slightly smaller than his own with breasts, even the shell is smaller, and his baby blue eyes. He pulls the hair, realized that it was real, and begins to hyperventilate.
Splinter awakens with the thought that something is wrong. He checks Mikey's room, sees that his son isn't there, and then checks the bathroom where he hears crying. "Michelangelo, what is wrong my son?"
A voice softer than normal replies, "Daddy something bad has happened to me."
"What is it my son?" the voice speaks softly.
"I…I…I can't", replies a very scared voice.
Finally after about 30 minutes Splinter gets his crying son to come out, and what he sees shocks him. "How?" Splinter asks after two minutes.
"I don't know, I woke up from a weird dream/ nightmare, came into the bathroom, and couldn't believe what I saw."
"Come, come I'll take you to Donatello's lab, and come back with your brother."
They walk to Don's lab Splinter trying to comfort his baby by rubbing circles on her shell. They walk into Donnie's lab/infirmary; he sits Mikey on a cot, and leaves. His mind is full of questions that can wait for now. "Donatello" he softly whispers in his ear hole. Donatello slowly wakes and looks at his father.
"Master what is wrong?"
"Michelangelo is in your lab come quickly and quietly."
"Yes Sensei."
They go quickly and quietly to Don's lab. Splinter opens the door for both of them. They hear Mikey crying, softer than usual for Mikey, he's rocking himself, and it looks like he has a cover on. The father and son duo walk slowly towards him, Splinter gets there first and softly whispers, "No matter what happens I love you my child." Don looks at him questionably as he hugs Mikey and leaves.
"Okay Mike what's wrong?" asks Don gently.
Mikey looks at his older brother with tears coming from her eyes and stands saying "Donnie what happened to me?"
Donnie hugs his younger brother shushing him, well her now, saying "Its okay I'll figure it out" softly churring to her. "Let's start with some blood work."
Mikey nods and offers her arm for the blood work, after some coaxing at first. Don takes 3 vials of blood and starts running chemical tests, hormone, etc. He looks over at a tired Mikey, "Get some sleep, I'll wake you when I have an answer."
She lies down on the cot, and Donnie covers her up. An hour later Mikey sits straight up in a cold sweat and on the brink of hyperventilating. Donnie rushes over from his research to take Mike in his arms, she flinches and tries to move away, but Don grabs her, pulls her in close, and rocks back in forth rubbing her shell. "Shhhhh it's just a nightmare."
"Will… will you… guys hate me…if I'm… stuck… this way?" she asked through her sobs.
"No, no way we will always love you no matter what. We may be more protective, but we will never hate you. This may be something out of your control."
"Okay, find out anything."
"Yeah, but you want to hear it now or with the others."
"With the others" Mike said sleepily.
And she slept in her brother's arms without any nightmares. Don kept up his silent vigil until he heard the others wake up, and walk towards his lab. He gently started to wake Mikey up.
Raph and Leo walk downstairs, they go towards the kitchen, but stop when they see Splinter outside of Don's lab. They both rush over thinking that Mikey's fever came back. "Master Splinter is Mikey's fever back?" they both asked.
"No my sons it hasn't, Donatello is with him now, but something has happened."
"Yeah and it's something big so before we go into the lab please stay calm because Mikey is really upset", says Don.
"Okay", Leo and Raph said with a worried tone.
They all walk into the lab, Leo and Raph looked shocked as they see their youngest sibling is no longer a boy but a girl, she starts to cry, and Splinter goes to hug and comfort her. Raph comes over to his sister and gently rocks her and Leo churrs softly until she is calm. In the meantime April and Casey have walked in and they are stunned.
"Well good since we are all here this will make explanations easy. Okay first things first as we all can see Mikey is now a girl, and no longer sick I may add. In nature some reptiles and amphibians will change gender if there are more of one gender, in this case Mikey turned into a girl because we are all guys. Also I am going to say that this permanent since this is something that is more nature instead of a mutation. This change was brought on by one of us needing to mate to create more of us. Lastly this is the reason why Mikey has been so sick lately. Any questions?"
"Why Mikey?" asked April.
"I think it happened to Mikey because even as a male her hormone levels that are higher in females were at an equal level to her male hormones, so if we had a female or two like us Mikey would have been fine but since we didn't her female hormones spiked causing her illness and transformation."
"I'm so sorry Mikey", Leo and Raph say.
"You both are in mating heat?" Don asked.
"Yeah."
"It's okay", Mikey said with a smile that is more innocent than before, "as long as you guys don't hate me."
"We could neva' hate ya sis", Raph said still hugging her.
"We will just be more watchful," stated Leo.
"Okay but she still needs a new name," Casey said.
"I've already looked at names," Donnie said, "Michelangela is almost the same with the exception of one letter and may help with confusion and make things easier."
"Um would you guys excuse us I think that Mikey and I need to have a female talk,' April said
They all nodded and left. The girls talked for hours while April tells Mikey about being a woman. All the time braiding Mike's hair and showing her how to do it at the same time. It became late in the evening and April and Casey left. After they left, the four turtles decided that it was time to go on patrol for the night.
"My children be extra careful out tonight, and watch out for each other, especially your sister."
"Yes Master Splinter."