Gwyneth Paltrow celebrated her birthday with her estranged husband Chris Martin over the weekend. The Iron Man 3 star marked her 42nd milestone with the Coldplay frontman, whom she spit from earlier this year following 10 years of marriage, and their two children Apple, ten, and Moses, eight, in the back garden of her home in Brentwood, California. A source told people.com: ”Gwyneth had a casual celebration during the day that Chris was a part of.” The celebrations carried on into the night as Kate Hudson, Matthew Bellamy and Nicole Richie joined the former couple for cocktails at the house. However, one person notably missing from the birthday bash was Chris’ rumored girlfriend Jennifer Lawrence, whom he started dating in late June. A source said previously of their blossoming romance: ”It seems they are definitely getting more serious. Whenever Chris is not spending time with Apple and Moses at his Malibu house, Jen is there.”