James Van Der Beek Marks Daughter Olivia’s 15th Birthday With Praise For Dawson’s Creek Reunion Performance: ‘Left In Awe’

James Van Der Beek is celebrating his daughter Olivia’s 15th birthday – and this one’s extra memorable for the actor because she’s now the same age as his character Dawson Leery was in the pilot episode of Dawson’s Creek.

In an Instagram post shared on Thursday. Sept. 25, the actor, 45, wrote, “My oldest turned 15 today. Same age that Dawson was in the pilot.”

In the video post, Olivia, whom he shares with wife Kimberly Van Der Beek, took to the stage to sing Paula Cole’s “I Don’t Want to Wait,” which served as the show’s theme song, at a Dawson’s Creek reunion charity event held on Monday, Sept. 22, at the Richard Rogers Theatre in New York City.

“To watch you stand there in that red dress, so confidently taking center stage amidst all those people I’ve known so long and cherish so deeply… I’m just left in awe,” Van Der Beek continued.

The event, which featured a live reading of the show’s pilot episode, was held in benefit of F Cancer in honor of Van Der Beek, who was diagnosed with stage 3 colorectal cancer last year.

Van Der Beek went on to describe how he’s seen Olivia grow. “I’ve always joked that you came out ‘parent proof,’ but this last year, as I’ve watched you accelerate into so many big decisions, jump into so many activities, budget your time, do your homework and your hair (which, from my point of view, seem to require roughly the same amount of time & focus 😂)… the less I think the parent-proof thing is a joke.”

He also reflected on a recent school sporting event, in which Olivia misinformed her dad about his ticket. In spite of the error, Van Der Beek said he was proud of his daughter’s reaction, referring to her mature approach as “something I’d like to THINK you learned from me.”

“You immediately took responsibility. Told me it was your first time doing all of it. Apologized succinctly, then did what you could to fix it. I was more proud of how you handled the mess-up than if you’d done it all perfectly the start,” Van Der Beek said of his daughter growing up.

He concluded the post by encouraging Olivia to “keep taking big swings” and “risk imperfection,” before encouraging her to “be true to who you are.”

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“Because, while only YOU will know exactly who your most authentic self will be, as someone who’s known you your whole life… I can guarantee you’re going to love her. Happy birthday kiddo. I love you ❤️,” Van Der Beek wrote.

While the actor was unable to attend the reunion in person on account of “two stomach viruses,” he appeared at the reunion via a pre-recorded video. Lin Manuel Miranda stepped in to read the role of Dawson Leery.

Dawson’s alum Jason Moore directed the event, which was produced by Carl Ogawa, Moore, Williams, Thomas Kail, Maggie Brohn, Kevin Williamson and Greg Berlanti. The original show aired for six seasons from 1998 to 2003, and tackled pivotal topics in the coming-of-age genre.

Van Der Beek and Kimberly are also parents to daughters Annabel, 11, Emilia, 9, and Gwendolyn, 6, and sons Joshua, 13, and Jeremiah, 2.