The American Idol season 5 runner-up, 35, attended her stepdaughter’s New Year’s Eve nuptials on Tuesday night alongside husband David Foster (Erin’s Grammy-winning father) and numerous other friends and family members of the bride and her new husband Simon Tikhman.
As seen on the Instagram Stories of the social media platform’s Vice President of Global Partnerships Charles Porch, during the evening, McPhee serenaded guests during what appeared to be the reception portion.
And that wasn’t the only standout musical moment of the night. Other videos shared by Porch showed Kate Hudson performing for Erin, 37, and her new husband, as well as the bride herself busting out some vocals as she led a group karaoke rendition of TLC‘s hit 1999 empowerment anthem "No Scrubs."
Other guests in attendance included Erin’s dad David, 70, mother Rebecca Dyer and her older sister and business partner, Sara Foster. Additional famous faces on hand to celebrate included Rachel Zoe and Jonah Hill, as well as makeup artist Aliana Lopez.
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For the nuptials, Erin wore a long-sleeved white dress with an open back and her hair in a chic updo, as seen in footage shared to Lopez’s Instagram Story.
Wedding guests stayed at the Graduate hotel and the ceremony was held at a house about 40 minutes away, where Erin’s father walked her down the aisle.
Lopez’s Instagram videos also showed the newlyweds having what appeared to be their first dance and being lifted into the air for the Hora, a common traditional chair dance at Jewish weddings.
RELATED VIDEO: David Foster’s Daughter Calls Katharine McPhee ‘Amazing’ After Pair Spotted Walking Arm-in-Arm
Erin and McPhee seem to have a close relationship, if a comment the comedy writer and Barely Famous star left on her dad’s Instagram in summer 2018 is any indication.
“Mommmyyy,” she jokingly addressed McPhee, alongside a sea of heart emojis following news of the singer’s engagement to David. Erin also previously posted on her Instagram Stories, “Excited about my new stepmom.”
In all seriousness, Erin — who attended the wedding of her father and McPhee this past June — has praised McPhee as “amazing,” telling PEOPLE in 2017 amid reports the two were dating, “I really like her. She’s awesome.”
Erin continued, “My dad is kind of a hopeless romantic, and Katharine’s awesome. We really, really like her, and we’ve known her for a really long time. And if he’s happy, we’re happy.”