The pair have been self-isolating together with their three daughters

Bruce Willis, 65, and Demi Moore, 57, have been fitting in plenty of family bonding time these past few weeks while self-isolating together with their daughters Rumer, 31, Scout, 28, and Tallulah, 26.

Although the couple divorced in 2000, a Moore source tells PEOPLE it’s not unusual for the two, who were married for 13 years, to spend time together.

bruce willis, Demi Moore
Credit: Tallulah Willis/instagram

“Demi and Bruce have been best friends for years. They are very close,” says the source.

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The Moore-Willis crew have been sharing social media updates about their time together during the coronavirus crisis, including an impromptu concert with all three girls singing while Scout played the guitar, as well as Willis shaving Tallulah’s head. Moore also posted a photo of herself and Willis with their daughters in matching pajamas and captioned it “family bonding.”

Willis, who married model Emma Heming, 43, in 2009, has been apart from her and their two young daughters, Mabel, 8, and Evelyn, 5, who have been staying at their L.A. home.

Bruce Willis and Demi Moore
Credit: Phil Faraone/VMN18/Getty

But despite the distance, a friend of the family says “everything is great” between
Willis and Heming: “Demi and Emma are close, and all three get on great as a big blended family. There are no issues at all. Emma needed to stay in L.A. with the young kids.”

In her memoir Inside Out, Moore wrote about the importance of keeping the family united after divorce.

“I think Bruce was fearful at the beginning that I was going to make our split difficult, and that I would express my anger and whatever baggage that I had from our marriage by obstructing his access to the kids. But I didn’t, and neither did he,” she wrote.

“We managed to move the heart of our relationship, the heart of what created our family, into something new that gave the girls a loving, supportive environment with both parents.”