The “Ain’t No Other Man” songstress paid tribute to her partner of eight years, sending the new 32-year-old birthday love in a series of posts — one of which included a romantic shot of a makeup-free Aguilera wrapped in Rutler’s arms.
“Birthday boy🎈…to a wonderful father, loving man and hardest worker I know,” she wrote, captioning a black and white version of the photo.
Another post, to her Instagram Stories, showed the same picture in color with the addition of flower emojis and the label “birthday boy.”
Aguilera, 37, also shared a throwback photo of her and Rutler, taken back in 2014 when she was pregnant with their only daughter, Summer Rain (who turns 4 in August).
“Summer inside” she wrote on the snap, with arrows pointing to her belly.
The picture shows Aguilera laying on her backside, and a shirtless Rutler leaning over to kiss her.
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In addition to Summer, Aguilera is also mom to son Max Liron, 10, from her first marriage to husband Jordan Bratman, which ended in 2010.
“Having children is the ultimate joy, and I love my kids, but women have to find time to nurture themselves,” said the former Voice coach. “If someone has a baby, the first thing I’m like is, ‘Okay, are you taking care of you?’ “