TMNT Boyfriend Scenarios

Good book idea?

So I had this idea for a book where the brothers have a little sister. She wants to have a normal family but it's hard. So the brothers are going to try to be like a normal family. Please tell me what you think.

3rd person POV:
"So tell my about this sister of yours," said Rockwell. The Mutanimals and the brothers were having their weekly meeting.
"Well," said Donnie. "Her name is-"
"ASHLEY!" Mikey butted in.
"She's almost 13 years old," stated Leo. "We found her under the freeway when she was a baby. She was about dead-"
"BUT WE SAVED HER!!" Mikey yells.
"Shut it Mikey," snapped Raph.
"During the Kraang takeover, they got to her." said Donnie. "They did tests and things that we don't really know about. Whatever it was, it caused her amnesia. So now-"
"They don't let me out of their sight. They aren't my brothers, they're my generals. I have no freedom. They drive me to school, and pick me up. I'm not aloud to go outside. I don't get to train." stated Ashley.
"Ash, you're not aloud in the meetings. You know that," said Leo.
"It's about me!" she argued.
"Ash....." Raph threatened pointing to her room.
"Ugh!" she grunted and stomped to her room.
"She's really delicate. She gets hurt easily." stated Donnie.
"Once she broke her arm by falling of the bunk bed!" Mikey butted in again. "Now, we check her health everyday. We know about problems before they happen. We check blood, weight, x-rays, everything." Continued Donny.
"Very controlled," Rockwell says in approval.
"Gotta keep her safe," said Slash nodding.
"She's a lot of work," commented Raph. "We promised Splinter we would take care of her."
"Have you had any issues?" asked Rockwell.
"Oh yeah," said Raph sounding annoyed. "She gets these stupid ideas from school about puppies, family vacations, having friends over, and BOYFRIENDS!"
"Her worst fear is needles. It makes it very hard to do lab work," stated Donnie.
"She doesn't follow directions," Leo comments.
"How does that work? School?" asked Leatherhead.
"Mr. O'neal talks with her teachers, but we can sign her tests and things." said Leo.
"So much work! If we get a kid, we are getting a boy," Slash states.

PLEASE REMEMBER TO TELL MY WHAT YOU THINK