Photo: Katherine McPhee/instagram, Jon Kopaloff/Getty

Katharine McPhee’sbusy holiday season has left her with some “mom guilt.”
On Monday, the singer opened up about being away from sonRennie David, 22 months, while she and husbandDavid Fosterpromotetheir Christmas album.
The 38-year-old mom shared a photo on her Instagram Story this week where stepdaughter Jordan Foster, 36, holds Rennie as they pose for a photo with Santa.
“Thanks @jordiedos for taking Rennie along while mom and dad were on stage. Have strong mom guilt!” McPhee wrote.
Captioning each person in the picture, McPhee noted Jordan “looks hot” while “Rennie looks scared,” and teased “Santa looks drunk.”
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Katherine McPhee Instagram

Speaking to PEOPLE in May, David, 72, opened up aboutwelcoming son Rennie in his 70s.
“I’ve loved every single day,” he told PEOPLE. “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,” he continued. “Even though I’m working a lot now, I’ll cancel anything just to hang with him. It’s just different.”
Along with Rennie and Jordan, David is also dad to daughters Allison, 52, Amy, 49, Sara, 41, and Erin, 40, from previous relationships.
Jemal Countess/WireImage

“He’s so much fun,” McPhee told PEOPLE of their little boy. “We’re having such a great time, and we’re incredibly busy. We wish we weren’t traveling quite as much, but we get to take our little guy with us for most of this stuff.”
The couple also spoke about their son’s love for music as he’s already been showcasing hismusical talentson the piano and his electronic drum pad.
“We think [he’ll be musical], but we don’t know,” David said. “Kids, strangely, will do something for a while and then it’ll amaze you and then they just drop it and they don’t do it anymore. So we don’t know if the drumming thing is here to stay — I’d rather he have a tennis racket in his hand than a drumstick to tell you the truth.”
“But anyway, if he ends up being a drummer, that would be great too,” he concluded. “He loves watching our drummer, JR Robinson.”
source: people.com