By Lara Walsh
Jul 20, 2016 @ 10:45 am
Daniel Zuchnik/Getty

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.

Top notch swim-coaches.

A photo posted by Olivia Wilde (@oliviawilde) on

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.

Matching baby bumps. ✌️

A photo posted by Olivia Wilde (@oliviawilde) on

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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."