Bike for my niece (San luis obispo)

I am sorry I have posted so much, but a lot of bad things have happened and we could use help.
My niece maudie is a great kid, who is currently fighting a rare form of brain cancer where the survival rate is zero.
I was wondering if anyone has any bikes for a child 11 to thirteen years old.
She loves glitter and neon colors, disney but has also likes the boys bikes that look like dirt bikes.
Bless you