Katharine McPhee/Instagram; Inset: Amy Sussman/Getty Images
David Foster is enjoying time with his little boy.
In the snapshot, Foster holds on to Rennie as the baby boy sits on top of a counter. The musician, 71, has both hands around his son's waist to keep him from falling.
Baby Rennie wears a royal blue onesie and holds on to a toy in the picture while his dad sports a navy long sleeve shirt.
"My boys 🇨🇦🥰❤️," McPhee Foster writes on the photo.
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Related video: Katharine McPhee shares bikini photo 1 month after giving birth
While Rennie is McPhee Foster's first baby, her husband is already father to daughters Sara, 40, Erin, 39, and Jordan, 34, whom he shared with second wife Rebecca Dyer, and daughters Allison, 51, and Amy, 48, from previous relationships.
Last month, the Smash alum spoke to PEOPLE about her son, sharing that her child continues to be "advanced" in how quickly he's hitting developmental milestones.
"His little teeth popped out and it's fun because they popped up earlier than when they were supposed to. He's a much bigger baby than his peers, so it's kind of fun to have a baby who is growing so well," McPhee Foster told PEOPLE during the beach clean-up event with World Surf League Pure and Wildcoast.
"It all evens out," she added. "They all end up in the same place, but right now he's a little bit ahead of the curve. It's super fun to be like 'Oh, he's advanced.' But really you know that your baby is just the same as any other baby."
The Country Comfort star said "nothing has surprised me" about motherhood, and she wants future moms to know that it's a joyful experience to welcome a child.
"You get all the opinions from people, and your life is going to change and you're going to be tired, and yeah those things happen. My life has changed, but not really," said McPhee Foster. "What I mean by that is that it just feels like he was always here. My life has changed because I'm so much happier."