Bobbi Kristina Brown has been spotted wearing an engagement ring leading some to believe she\'s engaged to her 22-year-old adopted brother, People magazine said. Bobbi Kristina, 19, has been making headlines since Whitney Houston died in a Beverly Hills, Calif., hotel room last month at age 48. The singer\'s only child with ex-husband Bobby Brown was hospitalized twice for anxiety after Houston died of a possible lethal combination of alcohol and prescription drugs, TMZ said. Rumors immediately began swirling Bobbi Kristina has substance abuse problems of her own and her family wants her to check into rehab. She was photographed this week in Atlanta kissing Nick Gordon, a non-blood relative Whitney regarded as an adopted son and who lived at the Houston family home in Atlanta since he was 12. Days later, what looks like an engagement ring was spotted on Bobbi Kristina\'s finger, People reported Friday. \"Yes, they are engaged, but the family is trying to coax her away from it,\" a Houston family friend said. Cissy Houston, Bobbi Kristina\'s maternal grandmother, is furious about the relationship, TMZ reported, telling a friend, \"What they\'re doing is incestuous.\"