Nick Gordon "loved and cared" for Bobbi Kristina Brown.
Although Nick, 25, is currently subject to a lawsuit from his late girlfriend's conservators, who accused him of domestic abuse and stealing money, his family insist he has always loved her.
In a statement following Bobbi Kristina's death at the age of 22, six months after she was found unresponsive in a bathtub, Nick's mother Michele Gordon said in a statement to NBC News: "The passing of Bobbi Kristina is devastating to Nick and our family.
"Nick loved and cared for Krissi deeply, and he has suffered greatly each and every day they've been apart. Nick and our family are in mourning, and we ask that you respect our privacy. Our thoughts and prayers are with both the Houstons and the Browns during this difficult time."
Bobbi Kristina is the only child Bobby Brown and the late Whitney Houston had together.
Whitney - who died in 2012 - took Nick in when he was 12 years old and raised him as her own although she never formally adopted him.
Bobbi Kristina and Nick started dating after Whitney's death and even claimed to be married, although it was later revealed that they were not legally wed.
Nick has been accused of physically assaulting his girlfriend and robbing her of thousands of dollars.
In addition, court papers allege Nick misrepresented himself as Bobbi's husband in order to control the aspiring singer and limit her contact with other people.
The documents state: "[Gordon] often answered Brown's personal cell phone, would not allow her to make appointments without his approval, and manipulated her bank relationship so that he could access her money."
According to the lawsuit, Bobbi Kristina had made plans to meet with an unnamed individual on January 31 - the day she was found unconscious - after previously confiding that her boyfriend "was not the man she thought he was" but never made it to the meeting.
Instead, she "became embroiled in a loud argument" with Nick at her house, which ended with her "face down in a bathtub, with her mouth swollen and another tooth knocked out" before later being diagnosed with "global and irreversible brain damage."
No criminal charges have been filed against Gordon.
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