Sharing a photo of herself and husband Olsen exercising outdoors with their 2-year-old son River Isaac, Ruah, 32, writes, “There are four people in this photo, can you spot them all?”
The actress, whose baby bump is on full display in a fitted tank as she lifts weights, also shared a quote from Carl Sagan.
“For small creatures such as we, the vastness is bearable only through love,” she wrote.
Want all the latest pregnancy and birth announcements, plus celebrity mom blogs? Click here to get those and more in the PEOPLE Babies newsletter.
Ruah and Olsen met on NCIS: Los Angeles, where she plays Special Agent Kensi Blye. Olsen, 40, a former Navy SEAL, has acted as his younger brother’s stunt double on the CBS drama.
Eric and Sarah’s new addition, a baby girl who will join their 2½-year-old Wyatt Oliver, will arrive this summer, they announced in March with a sweet snapshot of their son gripping his mama’s growing belly.
— Anya Leon