i need some advice from curly parents out there.

My niece(age 8 ) has beautiful 3b curls. Her mom also has curly hair but has pretty much has damaged her hair to the point she keeps it short. she's always ripping on her curls in front of her daughter to point my niece is beginning to not like curls. Her mom has begin to straighten it (with heat and no protection). she brushes her hair dry adn dont even own a comb.

Her mom gets all her hair advice from people who have no clue about curly hair or dont like curly hair so tells her to straigten it. my niece's hair is becoming a fried damaged mess. She's not my child so I can't say, "stop destroying her hair".

How can I save my neice hair with out crossing the line?