getty (2) The Olsen Twins and Tamera Mowry-Housley
Tamera Mowry-Housley and twin sister Tia Mowry had a pretty busy schedule as the teen stars of Sister, Sister , but they did occasionally moonlight as babysitters to the stars — specifically Full House stars Mary-Kate and Ashley Olsen!
In her new memoir You Should Sit Down for This, Mowry-Housley takes readers through her life — from landing her breakout role to her stint as a talk show host on The Real. And in one special anecdote, she shares how the biggest twin actors of the '90s aligned as she and Tia watched over the Olsens.
It all happened when the Mowrys were on the Full House set with their little brother Tahj — who starred in 14 episodes of the TGIF sitcom from 1991 to 1995 — for an episode called "The Devil Made Me Do It."
"It was just for a moment. It was half a day. It was so much fun. I forgot where the mom had to go, but I love the fact that she trusted my sister and I to take care of them," she recalls. "They had to have been, I want to say 7 or 8. They were very young. So sweet, so kind. I remember all they wanted was matzo ball soup."
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But that wasn't her last encounter with the twins. "We ran into them, I want to say, when they were young adults, like 20, 21," Mowry tells PEOPLE in this week's issue. "I couldn't tell them apart!"
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You Should Sit Down for This is out now.