Details are scarce but police reports from the US claim that her husband, who called for help, discovered Bobbi, 19, in the bath on Saturday morning.
Bobbi is now being treated at a Georgia hospital but police have not provided any updates on her condition because of medical privacy laws.
A statement released by Bobbi's father, Bobby Brown, the ex-husband of Whitney Houston, said: "Privacy is requested in this matter. Please allow for my family to deal with this matter and give my daughter the love and support she needs at this time."
Many outlets are drawing comparisons between this incident and the death of Whitney in 2012. The late singer was found in a bathtub at a Los Angeles hotel in February.
Bobbi Kristina married husband Nick Gordon in January 2014.
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