Amy Winehouse was a star, even before she was famous. As seen in a new clip from the upcoming documentary Amy, which features the late "Rehab" singer crooning "Happy Birthday" at age 14, Winehouse was wowing people with her voice years ahead of her 2003 debut album, Frank

The footage, taken back in the '90s and posted to YouTube on Monday, June 29, shows the then-happy and carefree British star goofing off with her friends at a party for pal Lauren Gilbert. Midway through the clip, the girls break into a rendition of "Happy Birthday" — out of which emerges Winehouse's rich and unmistakable warble. 

As she sings, the other girls fall silent, letting the "Valerie" performer take center stage. She ends on a high note, raising her arm in a dramatic flourish. 

Directed by Asif Kapadia, Amy chronicles Winehouse's journey from a young unknown to a troubled superstar, focusing on her life and subsequent death at age 27 in 2011. The film debuted at Cannes this year and is due out in theaters in early July. 

"I don't think I'm gonna be at all famous," she says in the trailer for the documentary. "I don't think I could handle it. I would probably go mad, you know what I mean? I would go mad." 

Winehouse's family has "disassociated" themselves from the movie, telling Us Weekly in a statement that it's a "missed opportunity to celebrate [the Grammy winner's] life and talent, and that it is both misleading and contains some basic untruths."

Kapadia, for his part, stands by the film. "We came on board with the full backing of the Winehouse family, and we approached the project with total objectivity," a rep for the documentary team told Rolling Stone, adding that they conducted "in the region of 100 interviews" with people who knew the singer. "The story that the film tells is a reflection of our findings from these interviews." 

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