Greece Getaway! Inside Kate Hudson's Vacation with Ex Matthew Bellamy and Mom Goldie Hawn

"They blend in with other families and honeymooners," a source tells PEOPLE

Photo: FameFlynet

For exes Kate Hudson and Matthew Bellamy, it’s nothing but calm seas – off a Greek island!

The pair have been toasting the start of summer on a family vacation in Skiathos in recent days with Hudson’s mom, actress Goldie Hawn, their 3 ½-year-old son, Bingham, and Hudson’s first child with former husband Chris Robinson, 11-year-old Ryder.

The group has been bunking in a villa while enjoying the 80-degree weather on Troulos Beach, a source tells PEOPLE.

“They blend in with other families and honeymooners,” the source says. “They are very focused on the kids and making it fun for them.”

The English musician, 37, was spotted playing cameraman for the mother-daughter duo on Tuesday as they got silly on the shore while posing for photos with friends Sophie Lopez and Kari DeLonge.

Hudson – whom, the source adds, is “in great shape and looks very happy” – wore a nude Acacia bikini and sunglasses. Hawn, 69, opted for a blue one-piece as she smiled next to her daughter.

The friendly exes were spotted paddling in a kayak on the water with Bingham between them. Donning another barely-there suit, Hudson then hopped off and swam alongside the boys.

The actress also spent some time in town, strolling and shoppingin a black strappy bikini top and printed maxi skirt. Wednesday on Instagram she showed off a gorgeous rainbow, writing: “Life isn’t about waiting for the storm to pass. It’s learning to dance in the rain.”

The former couple have remained amicable as ever after ending their engagement in December, taking trips, going on lunch outings and working on their wine company together in the months following their split.

“We’re family for the rest of our lives, we have a beautiful baby and we love making wine. We’ll continue doing it,” Hudson told Wine Enthusiast in March.