Bobbi Kristina is fuming with her grandmother Cissy Houston for filing legal documents with her mom's estate.

Bobbi, 19, is the daughter of late singer Whitney Houston, who passed away in February.

Matriarch Cissy recently filed court papers requesting that payments made to Bobbi from Whitney's estate be altered.

Apparently Cissy believes that her granddaughter is unable to make wise decisions about how to use that money.

"Bobbi is extremely angry at her grandmother for filing legal docs asserting that she is essentially hanging around with losers and [drug] users," a source told Radar Online.

"Cissy has made it known that she is extremely unhappy with the presence of Nick Gordon, Bobbi's 'boyfriend/brother' in her granddaughter's life. Right now Bobbi has absolutely no contact with her, Cissy or her aunt, Pat Houston. If Bobbi has concerns about payments from her mom's estate, she calls her lawyer."

The website reported previously that Whitney's estate trustees brought up the matter with the Fulton County Superior Court in Atlanta.

The documents claim that Bobbi Kristina "is a highly visible target for those who would exert undue influence over her inheritance and/or seek to benefit from respondent's resources and celebrity."