The ABC News star is a mom-of-two

Lara Spencer was overcome with emotion on Tuesday as she celebrated her son Duff's milestone 21st birthday.

The Good Morning America star marked the occasion with a series of photos of her son throughout the years, including some unearthed childhood snaps.

VIDEO: Lara Spencer's Family Life

It showed how much Duff had grown, having inherited his mom's kind face and shock of blond hair, with one picture of him beside his dad and Lara's ex-husband David Haffenreffer even showcasing how tall he was.

Despite the happy memories, the day was still bittersweet for Lara, as she was away from her son while he was able to celebrate the day at his university.

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"This kid is 21 years old!! Happy birthday to my favorite boy in the world. I cannot wait to celebrate with you in person. I love you," she captioned her post.

She was immediately inundated with a barrage of supportive messages and wishes for Duff, with one fan commenting: "They grow up too fast!!"

Lara celebrated her son Duff's 21st birthday while he's away from home

Another echoed the sentiment, saying: "He is so handsome! How do they grow up so fast!" while a third gushed: "Looks like his momma."

Duff moved to Dallas in 2021, enrolling at Southern Methodist University, a 25-hour drive away from his parents in Connecticut.

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Lara is also mom to younger daughter Katharine, who is set to leave the family home for college in a few months as well, most likely Vanderbilt University.

In an exclusive interview with HELLO! last year, the star opened up about her close relationship with both her children and how grateful she was that her youngest, Katharine, was still at home - for now.

The 21-year-old is studying at SMU in Dallas

When asked how she was feeling about her daughter's plans to go to college, Lara confessed: "We have one more year. I'm so thankful."

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