The singer's two daughters helped decorate for the intimate party.
Harbour turned 45 on Friday, so Allen and her two daughters -- 8-year-old Ethel and 7-year-old Marnie -- went to work decorating their home for an intimate party. A collage posted on Harbor's Instagram on Saturday shows a table full of delicious desserts, including dinosaur-adorned cupcakes and a three-layer cake, baked by Allen.
"To all the friends and fans that reached out with birthday wishes yesterday, thank you, so happy to have so so so so many people out there tracking my race to being infirm and embarrassingly saggy all over. And to those that didn’t, you’re heartless jerks," Harbour jokingly captioned his post.
"Very happy the supply lines still manage to ship dinosaur toothpicks. A birthday isn’t the same without an extinct species menagerie atop lush radioactive fluorescent green icing. I feel like a quarantined kid again, on the verge of a 10,000 year ice age. Hey triceratops! Looking trim!," he continued, adding, "Yo @paul.hollywood , call @lilyallen for baking tips."
Allen, meanwhile, shared a close-up pic of her cake, alongside a simple but sweet message for Harbour: "HBD @dkharbour."
Allen split from her ex-husband, Sam Cooper, in 2016, and their divorce was finalized two years later. She and Harbour have been romantically linked since last October. They later made their red carpet debut as a couple in January at the 2020 Screen Actors Guild Awards. Harbour and Allen sparked marriage rumors last month when he referred to her as his "wife" on Instagram Live -- though Allen clarified they hadn't yet said "I do."
"You think you married a pop star? You didn't," Allen said at the time. "Not that we're married. We're not married. I just want to make sure you know."
"But she is my wife, my wife," Harbour interjected, as Allen followed up with, "We do pretend."
See more in the video below.