This isn't all that her heart can hold.
"I would love to have another baby, but we'll see," Katharine told host Jennifer Hudson. "We're not in any crazy rush, but I hope so."
And while the two aren't jumping to add another kid to the mix, Katharine shared that she's been enjoying her new baby bliss, saying, "I love being a mom, I really love it."
After the 41 year-old TV host asked Katharine if her son can sing "like his mommy," she replied, "So far I would say his singing isn't his strong suit. I mean, he's under 2, so I'm not trying to be too critical here."
Although he isn't on his mom's level just yet, Rennie has proven he's following in his parents' footsteps when it comes to music.
In August, David shared a clip of Rennie tapping away on an electronic drum pad with his wooden drum sticks, which he captioned, "Is this normal for a 17-month-old?"
Previously, David—who is also a dad to daughters Allison, 52, Amy, 49, Sara, 41, Erin, 40, and Jordan, 36—has also opened up about why he doesn't regret welcoming another child in his 70s.
"I haven't regretted a single day of it," he told People last October. "I've loved every single day."
He continued, "It's the standard thing of like, 'Oh, well you were so young when you had your children and you were working day and night, you never saw them.' And there is some truth to that, sadly, for my [older] kids. I was just working a lot."
Whether or not they choose to expand their family is still up in the air, but it's clear both Katharine and David love the role they play as parents.