Mandy Mooresays her son is already surprising her!

After Kimmel, 54, showed a photo of Moore and husbandTaylor Goldsmithholding Gus as he stared down his birthday cake, the mom of one explained that things didn’t quite go as she expected.

“I was so excited to get him in front of a cake and the quintessential first birthday, smashing the cake everywhere,” she said. “Couldn’t have cared less about the cake.”

Joking that her son was “not a sugar guy,” theThis Is Usstar continued, “He was curious about it, but much more interested in the cheese board that Mom had for the adults.”

Mandy Moore Instagram

Mandy Moore Celebrates Son Gus' 1st Birthday

Moore, who welcomed her first child last February, also revealed why she and Goldsmith chose the name August for their son.

“My husband’s birthday is in August, we found out we were having a boy in August … but I also, having an alliterative name myself, I really liked having a Gus Goldsmith,” she explained. “Feels good.”

As Moore celebrates her son’s milestone birthday, the actress is also marking the end of a chapter with the final season ofThis Is Us,which is currently airing on NBC.

Jimmy Kimmel Live/Youtube

Mandy Moore on Final Season of This is Us, Her Son Gus’ First Birthday & Never Being a Bridesmaid

“My emotions are already right on the edge, but all of us are starting to accept that the end is near,” she said. “Like this is the last time we’ll be in this location, or perhaps doing a scene with this person. It’s so sad.”

The cast of This Is Us.Joe Pugliese/NBC

THIS IS US

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The star also opened up about directing an episode in season 6, telling Kimmel thatThis Is Uscreator Dan Fogelman gave her the opportunity after he asked the cast who wanted to direct and write episodes in the final season.

“He let it all happen … It was fantastic,” she said, although she noted, it “was strange to have to direct yourself while you were acting.”

Moore continued, “We have the most incredible crew, the most incredible cast, and I have even more affection and respect and affection for everybody after being in the director’s chair … There is not a bad apple in the bunch — I swear — across the board.”

Although the show is coming to a close, Moore said she plans to take a piece ofThis Is Uswith her to remember the experience.

source: people.com