Bobbi Kristina has always dreamed of following in her famous parents' footsteps -- but at what cost?

Though there have been unconfirmed reports of drug abuse on the 19-year-old's behalf, her father, Bobby Brown, told MTV News Tuesday that she's 100 percent sober and focused on her career.

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"Any parent that has a teenager in their life, they go through things. They go through phases that they might not be doing exactly what you want them to do in life, but they grow out of it, and my baby girl has grown out of it," Brown said. "I trust and believe that she's smart enough to not go down the same road that maybe I did in the past or her mother did in the past. She's extremely smart."

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Brown also denied rumors that Bobbi Kristina is hoping to change her surname to Houston. "She can't change her last name; her name is her name. She'll forever be known as Bobbi Kristina Brown," Brown said. "There's no changing that. There's no taking that back."

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The "My Prerogative" singer, 43, added that Bobbi Kristina will "forever be my baby girl. She's doing what she's doing, and I'm extremely proud of her."

He said: "She's acting and she's working on music and she's doing what she has to do to recover from her loss -- our loss."

This article originally appeared on Bobbi Kristina Is "Smart Enough" to Avoid Drugs