Olivia Wilde and Jason Sudeikis Are "Top Notch Swim Coaches" for Son Otis

Learning how to swim is a big milestone in any kid's life, and Olivia Wilde and Jason Sudeikis decided to show their 2-year-old son, Otis, the ropes while catching some sun in their pool Tuesday.

"Top notch swim-coaches," the 32-year-old actress captioned an adorable Instagram shot. In it, the expectant mom bares her growing baby bump in a red bikini and relaxes on a watermelon float while her 40-year-old comedian husband—stomach down on a flamingo float and dressed in red swim trunks—plays with their little boy.

While it looks like young Otis is getting the hang of navigating the water, something tells us that the soon-to-be parents of two perhaps didn't expect him to get in the pool. Instead of a swimsuit, the tot is dressed in a blue-and-white-striped T-shirt and blue shorts as he wades on a step.

The couple first announced that they are expecting their second child in April with a sweet black-and-white mother-son Instagram shot of the brunette beauty and her son cradling their bare tummies, which she captioned, "Matching baby bumps."