The Houston family made the announcement through a statement from their rep.
The statement says:
“Bobbi Kristina Brown passed away July, 26 2015, surrounded by her family. She is finally at peace in the arms of God. We want to again thank everyone for their tremendous amount of love and support during these last few months.” 
The daughter of late Whitney Houston died a few days short of six months after she was found unresponsivein a bathub in her Roswell, Georgia, home on Saturday, Jan. 31. Since then, she had been in coma and was being kept on life support following her near-drowning. In March she was moved to a healthcare facility in the Atlanta area.
She was in June transferred to hospice after her condition “continued to deteriorate,” Pat Houston said in a statement on behalf of the Houston family at the time.
A Brown family source revealed that Bobbi Kristina was “skin and bones” just prior to moving to hospice.
“She has been losing weight, she’s been losing hair. They were taking good care of her, but she has no muscle tone at all. There has been some worry that her organs are shutting down,” the source said.