Katharine McPhee Sweetly Kisses Son Rennie, 3, as She Celebrates Husband David Foster's 75th Birthday: 'My Whole World'

The couple welcomed son Rennie in 2021

Katharine McPhee Foster is sharing a sweet moment with her son.

On Sunday, Nov. 3, the actress, 40, posted a sweet photo of herself and her 3-year-old son Rennie on Instagram as they sat on some stairs together, next to McPhee Foster's husband David Foster, 75. In the photo, McPhee Foster shares a kiss with Rennie, wearing a blue jacket around her shoulders and bending down to reach her son.

Rennie wears a striped long-sleeve shirt and brown pants, facing up at his mom. "My whole world in one photo 🤩💕#hbd @davidfoster," McPhee Foster wrote in her caption.

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Related: David Foster Reveals Why Son Rennie, 3, Is 'Taking a Break' from Drumming: 'You Can't Push Them' (Exclusive)

Foster and McPhee Foster married in 2019 and welcomed their son Rennie in 2021. Foster is also dad to daughters Allison, 54, Amy, 51, Sara, 43, Erin, 40, and Jordan, 37.

In May, McPhee Foster celebrated Mother's Day with a sweet throwback photo on her Instagram Stories of her son Rennie after she gave birth. Sitting in a hospital bed, McPhee Foster could be seen holding her newborn, gazing down at him.

"In honor of Mother's Day, share your first picture with your baby 🤍," McPhee Foster wrote across the photo. "The best day of my life."

Last October, the musician mom shared a hilarious moment where she was horrified to discover she'd left her toddler son's iPad in the oven, where she had temporarily hidden it before.

The scene unfolded in a video shared on McPhee Foster's Instagram Stories, with her captioning the video, "Just over here cooking iPads," wrote adding facepalm emojis. "I tried to hide it and forgot it was in there while [heating] up the oven for my chicken special."

"The iPad is in the oven because he kept asking for it," she explained as she assessed the situation, while the toddler said, "Help me, Mommy," as he realized what happened to the device.