02/04/2012 at 12:20 PM EST
Life goes on!
As mom Demi Moore seeks treatment
, daughter Tallulah
celebrated her 18th birthday with a bash on Friday.
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.
Joining her: her sister Rumer
and Bruce's pregnant wife, Emma
, who was spotted hugging the birthday girl several times.
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."