what to do

I'm thirteen, and my friend was raped by her father. What should I do?

L_123
asks:
I'm 13 years old and my friend didn't go into detail, but she said she got raped by her dad(or her stepfather). she didn't tell her mom "because she'd get mad" and didn't think it would matter since her parents are getting a divorce and she'll move away with her mom soon. she doesn't want me to tell anyone and refuses to tell anyone....