Green Card Sponsor threatening to ''cancel'' greencard

I have a friend who was sponsored by her mother for a greencard when she was 11. She moved out of the country to live with her father when she was 15 and has not been living with or dependent on her mother since. She returned to the US when she was 22 and lived here for 3 years. For the passed to years she has been residing out of the country and travels back intermitantly. She had an argument with her mother and now the mother is threatening to cancel her greencard. Is there any way the mother can actually do this? Or are these just baseless threats to scare the daughter into doing what the mother wants? Can a sponsor somehow have the person whose greencard they sponsored revoked?