It's that trademark Foster sister sense of humor again!
Legendary songwriter David Foster, 68, and Scorpion actress, singer and Broadway star Katharine McPhee, 34, recently got engaged during a trip to Capri after dating for more than a year. His daughters Erin Foster, 35, and Sara Foster, 37, weighed in on the situation in true Foster daughter fashion.
After David confirmed the news on Instagram with a photo of him and Katharine, Erin commented, "Mommmyyy ♥♥♥."
"Out of the country. What did I miss?" wrote Sara.
Erin and Sara, two out of David's five daughters and the product of his second marriage to Rebecca Dyer, are known for their dry wit and humor.
Stylist Jamie Mizrahi, who worked as a costume designer on Erin and Sara's reality show Barely Famous a few years ago, also responded with "Mommy!!!!!!!!!"
This will mark David's fifth marriage following his divorce from Yolanda Hadid last year.
Brody Jenner, whose mother Linda Thompson was David's third wife in the '90s and '00s, also weighed in with a simple, "Congrats!"
Spencer Pratt, who starred with Jenner on the reality shows The Princes of Malibu and The Hills, also congratulated David on his engagement.
A source had told E! News that "David's children are all very accepting of Katherine now, and are very happy for their Dad."
Erin and Sara reacted favorably but played coy last year while talking to E! News about the romance rumors involving David and Katharine.
"We love Katharine McPhee. We love our dad. We want our dad to be happy. We don't care who he dates...don't really care how old they are," Sara said, adding, "We don't know if it's her."
"Honestly, our friends in their twenties are trying to date him, so we're just proud of him for not doing that," Erin said. "He's like, 'I draw the line there.' I think thirties, forties is like a respectable age for a man in his sixties."