Sand castles and kids! Kourtney Kardashian and her children Mason, Penelope and Reign Disick, had the best time in Miami Beach with Kardashian family friend Pastor Rich Wilkerson on Tuesday, May 3.

While other Kardashian family members attended the Met Gala in NYC on Monday night, the sexy single mom, 37, stripped down into a sexy black one-piece by Onia and reveled in the Florida sunshine with her little ones.

Kardashian ventured into the Atlantic with her 3-year-old daughter in her arms. Penelope was dressed stylishly in a printed swimsuit by Mara Hoffman and a pair of tinted Ray-Ban aviators.

After their dip, the girls casually reclined inside their cabana and watched Mason, 6, and Reign, 16 months, have fun with Wilkerson.

Baby Reign was equally ecstatic about his big day at the beach. Doting mom Kardashian shielded her youngest from too much sun by dressing him in a pair of purple swim trunks and a white button-down shirt. Both, however, got soaked at one point by waves.

Like his mom and siblings, oldest Disick child Mason lived it up with Wilkerson, who rose to fame in 2014 after presiding over Kim Kardashian and Kanye West's Florentine nuptials. Wilkerson and his wife, DawnChere — who are currently stars of their own Oxygen network reality series, Rich in Faith — are good friends with Kardashian and her ex Scott Disick (who was absent from the Miami festivities).

Pastor Rich adorably threw little Mason into the shallow waters of the ocean and even let Penny and Mason bury him in the sand.

In a December 2015 interview, Wilkerson explained how his friendship with the Kardashians has evolved. "Kanye came to one of the services. I think people think it's crazy, but we just became friends. We still are. We are great friends and we talk often," the Sand Castle Kings author noted. "Anyone loves a good wedding, and we also talked about Jesus, which is who we serve. I think, for us, what we weren't prepared for was that anybody cared that we were at their wedding."

Late Tuesday, Kardashian tweeted a photo of Wilkerson at the beach, and thanked him for joining them. "Shoutout to pastor Rich!" she captioned a photo of the pastor surrounded by cameras.

Kris Jenner's eldest concluded the day by tweeting an adorable photo of herself in bed with the kids. "Last nights slumber party," she captioned the pic.

Sources confirmed to Us Weekly on Tuesday night that Kourt and her sisters Kim and Khloé will be in Cuba this week to film scenes for upcoming episodes of Keeping Up With the Kardashians. It's unclear whether other members of the famous clan will be joining the trio down in Havana.

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