"Top notch swim-coaches," Wilde joked, along with a cute photo of herself -- baby bump on full display -- and Sudeikis relaxing on rafts while Otis waded into the water.
It appears the expecting parents had some company on their pool day. Wilde's Vinyl co-star, Bobby Cannavale, shared some sweet snaps of his son, Rocco, in the same watermelon and flamingo rafts, just two days earlier.
But back to Sudeikis and Wilde, the pair couldn't be more excited to be expanding their family. And as for 2-year-old Otis? He's still figuring it out.
"He knows that it's something in an egg," Sudeikis told ET of his son's reaction to becoming a big brother, adding that Angry Birds had become a helpful took in explaining the incoming arrival. "We just used metaphors in the movie [to explain it to him]. That's all. We explain everything through the movie."