In what well may be the year's most A-list baby shower, Tobey Maguire's fiancée, Jennifer Meyer, celebrated the couple's upcoming arrival at a girls-only affair in Malibu on Sunday afternoon, PEOPLE reports in its upcoming issue.

Jennifer Aniston carpooled with Courteney Cox Arquette to get there, joining such other guests as Jennifer Garner, Kate Hudson, Demi Moore, a pregnant Bryce Dallas Howard and some 50 others.

Around the Meyer family pool and lawn overlooking the Pacific Ocean (Jennifer's dad, Ron Meyer, presides over Universal Studios), the women passed the time swilling lemonade and eating such organic hors d'oeuvres as sesame shrimp and chicken skewers before the buffet lunch and lavish dessert table.

"It was a very mellow afternoon," says one guest. "It was a totally easy breezy, chill shower. No shower games. No present opening. Just hanging out."

Not that there weren't gifts. The mom-to-be got goodies from L.A. baby boutique Petit Tresor and parenting advice from Hudson, her friend since childhood.

Disobeying the women-only rule, Spider-Man star and dad-to-be Maguire poked his head into the party around 30 minutes before it wrapped up, only to be showered – appropriately – with kisses.