Sutton Foster on Parenting Daughter Emily, 4, and Why She Kept Adoption Process 'Close to the Vest'

Sutton Foster also shares how becoming a mom helped her bond with her Younger costars who were also parents

Photo: Jamie McCarthy/Getty

Sutton Foster is opening up about mom life with her "tiny grown-up."

The actress and husband Ted Griffin welcomed daughter Emily Dale in 2017 via adoption after years of fertility struggles. Speaking with Parents recently, Foster, 46, recalls why she decided not to tell many people about their adoption process before officially welcoming their child.

"Because my daughter was adopted, I wasn't telling anyone about our process. So many things can happen with adoption. We were keeping it close to the vest," she tells the magazine. "During season 3 [of Younger], I had gone through fertility treatments and had confided in [costar Hilary Duff] and other coworkers, so everyone knew I went through that."

"Fertility treatments hadn't worked for us," says Foster. "Then our daughter was born, and I was at the hospital and I thought, 'I should probably let everyone know.' So I sent everyone a text with, 'Guess what?' and a picture of me holding Emily. Everyone was texting back, 'Oh my God! What's going on?' "

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Once she became a mother, Foster remembers how she and the other parents among the cast of Younger (which recently aired its series finale after seven seasons) would try to "out-cute each other" with adorable kid anecdotes.

"As for Hilary, she's incredible. She has three kids now and I don't know how she does it. We were always close, but when I became a mom, we got a lot closer," says Foster. "There were a lot of other parents on the show too. Peter Hermann has three kids, Debi Mazar has two daughters, Miriam Shor has two daughters. There was so much family. And we were like family."

"We were always showing each other photos and trying to out-cute each other with whatever happened over the weekend," she adds.

Updating on her daughter today, Foster says that 4 years old has "just been crazy."

"She exploded with imagination and creativity and vocabulary," says the proud mom. "She's like this tiny grown-up who lives in our house. It's so cool. And to experience life through your kid's eyes, seeing things as if for the first time, it's just so pure and innocent and incredible."

RELATED VIDEO: Sutton Foster on Daughter Emily: 'I Want Her to Find Passion in Something — Other Than Romance'

In 2018, Foster opened up to PEOPLE about their adoption experience, saying that she realizes "Emily was so clearly meant to be our daughter."

"Where IVF was full of disappointment and heartbreak, adoption was so clearly what was meant to be for us," she added at the time, mentioning two failed rounds of the fertility procedure that had led to a "breakdown."

For Mother's Day in May, the Hooked author shared a sweet gallery of photo with Emily, penning a sweet message to her biological mother: "This is my fifth Mother's Day as a mommy and I've never been prouder. Or more grateful, to a very kind, thoughtful young lady who made the brave decision to place her baby for adoption. To my daughter's bio-mommy, and to bio-mommies and non-bio mommies everywhere! Happy Mother's Day!"