Watts, who turned 48 on Wednesday, took to Instagram to share some birthday sentiments.
"Another birthday!! #eek But I think I'm younger than this #vintagestroller?? ? Not quite sure what's happening here," she wrote alongside an old pic of herself as a baby. "#eek #70's #photoop #oldschool #raisedbyartists."
"Happy Birthday Sweetheart," Schreiber commented on the post.
The pair's clearly close relationship is consistent with the statement they released after their split.
"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. 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," the Watts and Schreiber told ET in a joint statement on Monday.
"While we appreciate your curiosity and support, we ask the press to be mindful of our children and respect their right to privacy,” the former couple added.
Schreiber and Watts had been together since 2005, and share two sons -- 9-year-old Sasha and 7-year-old Sammy.