Photo of Whitney Houston, Nick Gordon, and Bobbi Kristina posted by Bobbi Kris to Twitter after Whitney's death in February.

Is it okay to hook up with your adoptive brother?

That's the question everyone's asking after reports emerged that Whitney Houston's only daughter, 19-year-old Bobbi Kristina Brown, is romantically involved with 22-year-old Nick Gordon, who Whitney unofficially adopted a decade ago, and who's been like a brother to Bobbi Kris. reported last week what the two were spotted kissing and embracing in a Target near their Atlanta home, and now the rumors have been confirmed (at least obliquely) by both Nick Gordon and RadarOnline.

Nick Gordon tweeted the following:

Meanwhile, Radar quoted anonymous family members as saying that they wouldn't be surprised if the two recently struck up a romantic relationship. also quotes expert family therapist Dr. Phil Dembo as saying that even though there is no blood or legal relationship between Bobbi Kristina Brown and Nick Gordon, the romance still has the feel of an incestuous dynamic.

Could this be why family matriarch and Bobbi Kris's grandmother Cissy Houston is so intent on keeping the two apart?