updated 02/04/2012 AT 12:20 PM ET
•originally published 02/04/2012 AT 12:45 PM ET
Life goes on!
The party took place at dad Bruce Willis’s Beverly Hills mansion, and it started in the late afternoon. Tallulah wore a tiara and appeared to be in good spirits.
Moore, meanwhile, has not been spotted since news of her health crisis broke. A source close to the actress says only a “very close” group of friends knows where she is. Says an insider: “Demi is such a private person and where she is now is being kept top secret.”