Sometimes moms deserve a little R&R on Father's Day, too.

After sending out a happy Dad's Day message to "all the amazing dads out there," Britney Spears shared a handful of Instagram pics from her "fun day sun day" by the pool and at the beach with friends on June 19.

Fun day sun day!

A photo posted by Britney Spears (@britneyspears) on

Looking happy and relaxed in a black bikini and matching black choker (yet another piece in her massive bikini collection), Brit-Brit lazed around on a chaise and took a moment to ponder the hills beyond the infinity pool where she and her companions were swimming.

Later in the afternoon, the "Toxic" singer posted a late-day beach selfie that showed her smiling in the sand just as the sun was starting to set.

"Great day 🐠🐠🐠🐠," she captioned the dreamy snap.

Great day 🐠🐠🐠🐠

A photo posted by Britney Spears (@britneyspears) on

It's understandable if Britney needed a little downtime over the weekend. According to the Daily Mail, she recently announced her "Britney: Piece of Me" Planet Hollywood residency in Las Vegas would be extended by four months and will now run through February of 2017.

E! News reports she's also in the process of finishing up a new album and working on a music video for "Make Me."

And last week, she released her 20th fragrance, the Hawaii inspired Private Show, which she's described as "soft" and "really soothing."

In spite of the flurry of new projects and performances, Britney also made time for some fun with her sons, Jayden James and Sean Preston, in Las Vegas, where their dad, Kevin Federline, had a DJ gig at a gentleman's club the night before Father's Day.

Great Vegas trip!

A photo posted by Britney Spears (@britneyspears) on

Kevin, who has four children in addition to the kids he shares with Britney, recently opened up to ET about his romance with the singer, which came to a close after she filed for divorce in 2006.

"It was so crazy," he said, referring to the paparazzi and tabloid headline-filled time the two spent together. "I look back at it and it's like, at times it was so overwhelming."