Watch a 14-year-old Amy Winehouse sing "Happy Birthday"

We're seeing a different side of Amy Winehouse in a newly released clip from the upcoming documentary, "Amy."

In the short snippet a 14-year-old Winehouse is seen belting out a version of "Happy Birthday" with her pals.

Filmmakers say the documentary, which screened at the Cannes Film Festival in April, was the result of interviews conducted with roughly 100 people who knew Winehouse -- ranging from friends and family to ex- boyfriends and industry folks.

Winehouse's family, though, is none too pleased with the doc. Family spokesman Chris Goodman said director Asif Kapadia's film is "misleading and contains some basic untruths."

The Grammy winner died in July 2011 at age 27 of accidental alcohol poisoning.

"Amy" surfaces in select theaters on July 3 before opening nationwide on July 10.