See Chrissy Teigen and John Legend's Cutest Snaps of 'BFF' Daughter Luna and Son Miles on Vacation

Fun in the sun!

Over the past few days, John Legend and Chrissy Teigen have been enjoying a family vacation with their two children — daughter Luna Simone, 4, and son Miles Theodore, 2½.

Seen spending time with one another in an undisclosed location since Saturday, Teigen, 35, first revealed that the family of four was heading on vacation when she shared a snapshot of herself and Luna posing together on a plane.

In subsequent photos shared in the days that followed, Teigen then posted pics of Miles lounging before a sunset with his mom, as well as a set of photographs of Luna playing on the beach, where she could be seen striking a silly pose with half of her body buried beneath the sand.

In another post shared by Legend, 42, on his respective Instagram account, the Grammy award-winning singer posted a picture of Luna and Miles standing on the beach in matching starfish-themed bathing suits. "BFFs," Legend wrote alongside the sweet shot.

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John Legend/Instagram; Inset: Allen Berezovsky/Getty

Chrissy Teigen/Instagram

Chrissy Teigen/Instagram

Chrissy Teigen/Instagram

Chrissy Teigen/Instagram

RELATED: Chrissy Teigen Says She's Still 'Coming to Terms' with Not Being Able to Get Pregnant Again

Late last month, in her latest cover story with PEOPLE, Teigen opened up about her children and her feelings that she'll "never" be pregnant again.

"Coming to terms with not being able to carry again is still really difficult for me because I feel so healthy. I'm like, why?" the Cravings author told PEOPLE. "But then I think about it as my uterus is just not cooperating with me — and it's not a failure."

Teigen and her husband welcomed their two kids via IVF, and "I'm so lucky for that," she said. "I just think of it in terms of how blessed I am already, and also there are so many ways to have a child nowadays ... whether it's surrogacy or adoption."

The star says she can't imagine a "life without more" children, and as she and Legend navigate their own reality, she hopes to help others in similar situations.

"For me what's really important is being able to make sure that everybody has access to those ways and making sure that people are able to make their dreams come true. It would just be a beautiful thing," Teigen said. "It's so incredibly expensive to freeze your eggs and to harvest them. IVF isn't an option for a lot of people and it needs to be. It shouldn't be such an expensive endeavor for a woman trying to conceive a child."

RELATED VIDEO: Chrissy Teigen, Pepper, Luna and Miles Grace Covers of PEOPLE's Beautiful Issue

Last fall, Teigen and Legend revealed devastating news that they had lost their third child, a son named Jack who was conceived naturally, at 20 weeks of pregnancy.

Currently building a new home, the stars are honoring their son with a special tree planted inside their house — and helping Luna and Miles foster memories with their baby brother.

"It's important for us in Thai tradition that we always embrace the ones we've lost, and they're never, ever gone. This tree being planted inside the home, the whole reason why I wanted it was so Jack's ashes could be in that soil and he could be with us all the time and grow through the beautiful leaves in this tree," said Teigen.

"The way Miles and Luna talk about him is so beautiful and reminds me of when I was little talking to my grandpa who was just sitting bedside next to my mom in a little urn," she continued. "It's all beautiful, and I love that tradition carries down."