“Hope you all celebrating had as chill a 4th of July as Naleigh and I,” the 37-year-old actress captioned her Instagram pic.
While her growing baby bump wasn’t in full view, Heigl and Naleigh were all smiles, mimicking one another in the same laid-back pose. “#Gratefulgirls #thisisthelife” the mom-to-be hashtagged the shot.
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Heigl just announced her first pregnancy with her husband of eight years, Josh Kelley. Their son, due in January, will join big sisters Naleigh and Adalaide Marie Hope, 4 — whom the couple adopted in 2009 and 2012, respectively.
“It was totally unexpected but thrilling,” Heigl wrote on her blog after sharing her exciting news exclusively with PEOPLE. “The whole pregnancy thing is new to me, but the thrill of having a baby is not.”
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“Naleigh and Adalaide are over the moon and [cannot] wait to spoil their new sibling rotten,” she wrote, adding that she and her singer-songwriter husband, 36, are “full of high hopes and bubbling anticipation.”
“This is truly an amazingly blessed time, waiting for the child you’ve been dreaming of to make their appearance,” she continued. “Though I’ve never been a particularly patient person, my experience of waiting for Naleigh taught me a lot in that department.
— Dave Quinn