Bobbi Kristina Brown has suffered ''irreversible brain damage''.

The 22-year-old aspiring singer was placed in a medically-induced coma after being found unresponsive in her bathtub in January, and though her father Bobby Brown recently revealed she is now ''awake'', her grandmother Cissy Houston - the mother of the young star's late mother Whitney Houston - says she is still ''unresponsive''.

Cissy said in a statement: ''I have just returned from visiting my granddaughter Bobbi Kristina in the hospital and while she is no longer in a medically induced coma she has a tracheotomy and according to the doctors she has global and irreversible brain damage and remains unresponsive.''

Cissy claims only a ''miracle'' will improve her granddaughter's condition and she has appealed for fans to pray for her family.

She added: ''Meeting with the doctors and understanding that she can live in this condition for a lifetime truly saddens me.

''We can only trust in God for a miracle at this time. Keep us in your prayers.''

Cissy's comments came after Bobby's lawyer confirmed that doctors have indicated Bobbi Kristina will have a ''long life'' but they are unsure of what the ''quality'' of it may be.

Christopher Brown said: ''Bobbi Kristina's condition has changed since moving from Emory University Hospital and there has been improvement. Doctors have indicated that she will have a long life.

''However, Bobbi Kristina is presently embarking on a rehabilitation process and the quality of her life will not be known for years to come.''

Bobby simply added: ''We thank everyone that supports Bobbi Kristina and God is hearing our prayers.''