The mother-son pair enjoyed a recent day of sun, surf and sand, snapping a photo together that the pregnant actress shared to Instagram over the weekend.
Luca, 6, is dressed in a gray tank top and swim trunks, looking downward toward his sand pail while Duff, 30, bares her baby bump in a black bikini top and green bottoms.
“My sweet sweet boy. Oh the adventures we’ve had 💙,” the Younger star captioned the image.
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Days later, the expectant mama headed to the luxurious Tomoko Spa for a pre-natal massage with a pal. “Had the dreamiest of nights with this babe,” she captioned a snap on Instagram.
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During an appearance on The Late Late Show with James Corden a few days after her announcement, Duff opened up about how Luca is preparing to be a big brother.
“The beginning was a little … he was surprised,” said the actress, adding that her son was “warming up to the idea” of having a baby sister and even has a name picked out already.
“Luca thinks ‘Cofant Croissant’ is like, the coolest name,” she explained, adding that he has become pretty insistent on the choice. “There would be no confusion. And when I just refer to it as ‘Cofant’ and I’m like, ‘That would be so cool, no one at school’s going to be named Cofant,’ he’s like, ‘Croissant. Cofant Croissant.’ It goes together. There’s no separating the two.”