Rumer Willis definitely didn't want to be the belle of the ball on Sunday night.
Less than a week after her mom Demi Moore's terrifying hospitalization, the actress, 23, snuck into the official after party for the Screen Actors' Guild Awards held in a tent outside the Shrine Auditorium in Los Angeles.
The star was "keeping a crazy low profile," an observer confirms to Us Weekly. "She definitely didn't want anyone to see her."
No wonder. It's been widely speculated that Rumer was among those present at her 49-year-old mom's home last Monday when frantic pals called 911. (At one point during the call, one woman seems to call out Rumer's nickname "Ru.") Newly single since her painful split from Ashton Kutcher last November, Moore suffered "convulsions" and after she "smoked something," a female caller informed a 911 dispatcher on the chilling tape.
"Rumer was like an apparition -- she just slipped in with a friend and then was gone," the SAGs reveler says. "She looked like she was walking on eggshells…She was just weaving through the crowd."
Rumer (the eldest of three daughters Moore has with ex-husband Bruce Willis) had been her mom's frequent party pal out and about in Hollywood in the weeks leading up to Moore's medical -- and emotional -- crisis.
"Because of the stresses in her life right now, Demi has chosen to seek professional assistance to treat her exhaustion and improve her overall health," her rep said last Tuesday.