The former couple, who announced their split 10 months ago after 11 years together, appeared to be all smiles as they helped Sasha cut his birthday cake in a photo shared to Schreiber’s Instagram account.
“Happy Birthday Big Boy!,” the 49-year-old Ray Donovan captioned the family shot. “Finally hit the double digits!”
Watts, 48, also wished Sasha a happy birthday on Instagram — sharing a shot of the blonde-haired boy while on their recent trip to Africa.
“Happy Birthday to this beautiful boy,” she wrote in the picture’s caption. “Sasha is 10 today. Here he is in Africa, living his dream. His love and understanding of nature is everything. So lucky to be his mummy such a [gift] #inhiselement #manofthewild.”
Watts and Schreiber — who are also parents to son Samuel Kai, 8 — announced they were going their separate ways in September 2016, having first met at the Metropolitan Museum of Art’s annual costume ball in 2005.
“Over the past few months we’ve come to the conclusion that the best way forward for us as a family is to separate as a couple,” they said in a joint statement to PEOPLE. “It is with great love, respect, and friendship in our hearts that we look forward to raising our children together and exploring this new phase of our relationship While we appreciate your curiosity and support, we ask the press to be mindful of our children and respect their right to privacy.”
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On Saturday, they took the kids to Comic-Con, where Watts was promoting her role in the Twin Peaks revival while Schreiber hit the photobooth with his sons — all three dressed in costume.
“There are good days and bad days and Liev and I are on great terms and we’re trying to do our absolute best for the sake of the children and we hope to keep moving forward in that way,” Watts told Vogue Australia in May.
“He’s fantastic dad, a wonderful, wonderful man, and we still want the absolute best for each other,” she added. “So, that’s pretty much all I’ll say.”