The rare photos of the family all together show them ringing in the milestone away from their home in New York.
The group had jetted to the UK where they did a spot of sight-seeing and also dined out together for her birthday.
WATCH: Lara Spencer makes difficult discovery at her family home
Lara called the adventure "perfect" and thanked London for it's hospitality. She looked delighted to be with her children and husband who were doting on her in the photos.
Their get-together is made even more special because Duff left home last year to head to college.
Lara recently opened up to HELLO! magazine about her daughter's college plans and shared her relief that she still has another year to go.
Lara Spencer was with her children on her birthday
When asked how she was feeling about her daughter's plans to go to University, Lara confessed: "We have one more year. I'm so thankful."
That's not to say she hasn't got a plan in place already. At the end of last year, the TV host confirmed her talented offspring had earned herself a place on the lacrosse team.
"SO proud of my girl Kate on her verbal commitment to play lacrosse at Vanderbilt University!!" the Good Morning America host wrote. "Kate-You dreamed it. You worked for it. And you made it happen. #proudmama #GODORES #Vandylacrosse."
Lara and her husband Richard McVey enjoyed their visit to London
Lara also revealed to HELLO! that while the COVID-19 pandemic was difficult there was a glimmer of light - and that was spending more time with her children.
"The impact of COVID on the kids and the world has been so tragic and difficult but there are little silver linings," she said.
"One of them has been to have more time with my children over the last few years. Being at home with them has really been cherished."
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