“When we got married, I didn’t know if we were going to get pregnant right away,” Smart tells PEOPLE in this week’s issue.
“That didn’t happen. Years went by and we were just on this roller coaster. Nothing was working. We started to wonder if we were ever going to be parents.”
Ultimately they opted to use a surrogate and welcomed their daughter in December 2016.
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“We are so grateful we are parents and that we have a beautiful, healthy daughter,” says Smart.
“But it was hard and the more that we can talk about it, the more that we can share our struggles, our difficulties, the more we can help each other and not feel alone in the process.”
Smart and Oosterhouse are raising their daughter in Los Angeles, but spend summers in Traverse City, Michigan, where they own a 100-year-old farm house.
“She’s a little explorer, and it’s so cool to watch her run around the yard and see her experience bugs and snakes,” says Oosterhouse. “She’s fearless!”
For more from Amy Smart and Carter Oosterhouse, pick up this week’s issue of PEOPLE, on newsstands now.