Demi Moore's Daughter Tallulah Willis Celebrates 18th Birthday at Dad Bruce's Home

Given all that her family has gone through in the last few weeks, it was time Tallulah Willis had a chance to unwind.

Celebrating her 18th birthday at the Beverly Hills, Calif., home of her dad Bruce Willis, Tallulah donned a tiara, white tank top and cutoff jean shorts to host a low-key bash for friends Friday.

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Though mom Demi Moore -- who was hospitalized Jan. 23 after suffering a seizure -- was nowhere in sight, Tallulah's older sister, Rumer, 23, stopped by for the party. The girls' 20-year-old sister, Scout, is away studying at Rhode Island's Brown University.

Tallulah has been staying with her dad Bruce -- currently expecting his first child with new wife Emma Hemming -- since her mom's medical emergency.

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"Things have been strained between Demi and [daughter] Scout and Tallulah for a long time," a source tells the new issue of Us Weekly. "For a while, Ashton [Kutcher] was acting as the primary parent because Demi was so out of control."

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As Moore recovers, Tallulah's father has begun to back away from his ex-wife. "Bruce and Emma made a conscious effort to distance themselves from Demi," a family source explains. "She's not a good influence, and Bruce and Emma want to keep things healthy."

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