Curly Hair help

Ok this isn't exactly for me.. I have pin straight hair so I don't seem to have this problem. BUT my niece is turning 14 and has extremely curly frizzy hair. She is half black and half white so her hair is soft but curly. She's just now starting to really care about trying to tame and take care of her hair and her birthday is coming up so I wanted to get her some good hair products. What are some of your hair routines and products you use for curly hair? I've heard about silk pillow cases so I'm going to get her those. Just want more ideas and advice to give to her.