Whitney Houston's only daughter Bobbi Kristina set to inherit first $1.2 million of mother Whitney Houston's $12 million fortune but her grandmother Cissy is worried the 20-year old will dwindle the money away.

The dramas of Whitney Houston's life seem to be continuing into her daughter's as Bobbi Kristina awaits the first $1.2 million installment of her inheritance.

The only child of Houston and Bobby Brown will inherit Whitney's entire $12 million estate by the time she turns 30, but her grandmother Cissy is worried the 20-year old will dwindle the money away.

This comes after the 80-year old branded Bobbi's marriage to 'adoptive brother' Nick Gordon, 24, as 'incestuous', after the two announced they had tied the knot on Twitter earlier this month.

Frowned upon: Her family is reportedly unhappy with her marriage to 'adoptive brother' Nick Gordon, who she tied the knot with this year

She then moved in with Nick - who was taken in by her mother and father but never legally adopted - into Whitney's Atlanta apartment despite Cissy's protestations, and her father Bobby's attempts to persuade.

Bobbi was six and Nick nine when he was brought into their family, and the two still reportedly use the nicknames 'Baby Sis' and 'Big Brudder' to affectionately call one another.

Disapproving: Cissy Houston is said to be worried Bobbi will waste the inheritance, and has reportedly branded her marriage to Nick as 'incestuous'

Bobbi has been flooding her Twitter feed with statements of love for her 'hubby' and talk of her burgeoning music career as she tries to make it as a singer and actress like her mother.

She is also reportedly hoping to start a family, as a source told Grazia magazine: 'They want to have a baby as soon as possible. After a tough few years, Bobbi wants a happy ending. But her 

grandmother is beside herself with worry.'

But now the