Save Her
Guys I came up with a new DPxDC AU where we get Deaged!Dani(Ellie), Mom!Cass, and Dad!Danny.
"Cass... Are you sure you want to do this?" Tim asked one more time before he would put the last code in. He knew she was sure, more than willing to deal with it but he just needed one more confirmation before they all started what couldn't be stopped.
Cass stared at Tim, her face straight and her eyes firm without a hint of doubt. She nodded in his direction, despite the growing nervousness in her stomach for a second even with Stephanie squeezed her hand in reassurance and support.
Cass turned her gaze to the little girl, no older than thirteen, suspended in a tank full of green glowing goo and asleep. Her vitals showing up on screens near the tank coming from the wires that were hooked up to her inside the tank.
She said her name was Danielle Masters but had also said she wouldn't mind a new name once she was no longer just a clone but instead Cass's new daughter. She had only asked to include her 'dad', a Danny Fenton/Phantom, in her future naming decision too
Cass took a breath and said softly but determined "Save her."
Tim nodded back and entered the final code into the computer.
-x-x-
Basically-
Cass, while in Hong Kong, finds a destabilizing Dani.
Cass see's the desperation and fear Dani is in and helps as best as she can.
She manages to help but they both seem to know the next time this happens will be Dani's last.
Dani is very, very sick at this point and needs help even standing up.
Cass see's and remembers herself at this age and wants to help.
They do become friends and learn each other backstories
Cass goes to the one person she knows who might to be able to help with the destabilizing clone problem.
Tim, Tim is that person. (Because he's friends with Conner, and no doubt knows Conner's DNA and how it works, AND the fact he tried his hand at the whole cloning thing.... Tim told Cass everything once things settled down after his BruceQuest was done)
They fill him in on what is happening and he starts helping, mostly cause Cass asked and because "Clone rights!" (side note, he asked if its okay to tell Conner, when yes, Conner comes over and chats with Dani the entire time whenever he has free time) (the image of Conner sitting at her bedside as they chat is in my head btw)
Tim finds out the reason Dani is destabilizing so badly is because she's not 'complete', she needs a female donor technically because she's female not male (unlike Conner who is stable because he is male with male donors)
They find out that after trying to see of ways to save her that Cass was the closest that could donate her DNA (they also discover there might be a connection between ectoplasm and the Pits, they don't wanna run the risk of asking a LOA member) (If I remember right Cass grew around the Pits for a while and was even tossed in them after a fight with Shiva)
Tim also brings them news that Danielle's body is rapidly destabilizing due to her body/hormones trying to 'mature' her since she is at that age and she has less than a week.
Everyone knows there is no time to think of trying to save her in any other ways.
Tim says that if they do this, they have to technically 'remake' her body to the actual age she is (a couple months old/a few years old? Depends on the writer) and there was a high chance of her not remembering her old self. That the male DNA in her, the one that seemed to be the most is Daniel 'Danny' Fenton's DNA will be considered father DNA and if Cass does this, her's will be the mother DNA. (Vlad's DNA, because he would try to put his own in, would be 'pushed out')
Cass would become Dani's mother.
Both Cass and Dani talk about it.
Cass wants to help her, she had become friends with Dani and loves her like a little sister already but will try to love her as a daughter as well.
Dani wants to live an actual life.
They agree to it.
Tim sets everything up, Conner is helping around/keeping Dani comfortable/happy.
Cass told Steph and Babs whats happening and they're helping/being supportive once they find out everything.
Meanwhile Tim and Babs has Dick, and Damian go to Amity Park to find out whats happening there/bring Danny to her so they can explain what happened to Dani. (Dick and Damian have no clue why just yet but will find out when they get back, but oh boy is Amity a mess between the GIW, ecto-acts, crazy fruitloop mayor/villain ghost, and other stuff)
Cass and Tim tell Jason and he's helping Alfred (who basically already knows) set up a room for the newest arrival. Jason is gonna stick around if to just see Bruce's face when he gets called a 'grandpa' for the first time.
Duke takes this all in stride when told and just goes along with things now because this is life with the Batfam. He also helps with the room and keeping Dani company until the day.
Bruce was on a space mission thus comes home to find a new group of teens with his kids. One (with black hair and violet/purple eyes) is talking about a purple back gorillas with Damian and swapping vegan recipes, another (wearing a red beanie and has glasses) is getting into tech talk with Tim and Babs, a girl with red hair is talking classic books with Jason and giving Duke advice with school and stress, and another boy (one who could pass as one of his own adopted kids) is cracking jokes/puns with Dick, and telling Steph stories about his Rogues(!?).
Bruce isn't ready when Cass comes up behind him, nearly dancing in her spot and hands him something.
He is given a baby/toddler that looks like Cass but had darker hair and bright blue eyes.
He almost faints when Cass signs to him that he's holding his granddaughter, her baby.
He does faint when Cass notices the signs and takes her baby back before he falls over.