Bobbi Kristina Brown, the daughter of U.S. singers Whitney Houston and Bobby Brown, announced via Twitter she has married Nick Gordon, her off-on boyfriend. "@nickgordon! #HappilyMarried," the 20-year-old reality TV personality tweeted Thursday, alongside a photo of her and Gordon's new wedding rings. "SO #Inlove. If you didn't get it the first time that is." Brown also hinted she and Gordon have even bigger news to share. "BIGGGG things in store guys . . . I'm so excited!" she wrote on Twitter Thursday. "We bouta change the world babbbbby! #bringEmOut! #Getready! xO!" The couple have had a stormy relationship for several years. Houston unofficially adopted Gordon when he was 12 and raised him as her son in the years before her 2012 death, UsMagazine.com said.