Whoa whoa whoa. Why are you using the name "son" and "charlie"? She's no longer your son anymore and you should stop referring to her as such. You say that you are okay with it but just from choosing to use all male pronouns in this post I doubt that. Seriously, this has been going on for probably quite a while now (three or four years is my guess) and you still refer to her as "You're son". Here is some perspective. I grew up in a very conservative and religious household. When I came out as transgender my parents accepted me 100%. They had a bit of trouble with pronouns at first but guess what? After about three or so months they never mis-gendered or used my old name. And they would never when talking to others refer to me as "their son". My parents who are one step away from voting for Donald Trump have accepted me in a way that you seem to have failed to do for your Daughter. I mean, look how much you use her old name in the post? Seriously.

Now onto the main issue at hand. Kelly is acting like a child. I would never ask my parents for money. I grew up mostly poor so I respect how much 20k is. Kelly seems to lack that understanding. Threatening suicide is not something anyone should ever do. Now I don't know if you are bigoted or not, if I had to guess I would say that you aren't. But Kelly might have built in her mind that she had a difficult childhood. It's quite possible she built up this victim mentality over the years to cope with transitioning. I did something similar though I never lashed out at anyone. It's really quite easy to feel sorry for yourself, but when it all comes down to it she is going to have to understand that she needs to buck up and stop being such a wuss.

I would suggest family therapy or at the very least therapy for Kelly. She probably is lost in her own world of pity and entitlement and needs to accept that the world is not fair. If she refuses to go to therapy with you, then you might want to consider establishing boundaries. Being transgender doesn't make you entitled to $20,000~ of your parents money.

Good luck.