Lin-Manuel Miranda has joked standing in for James Van Der Beek fell under his "godfather" duties.
The theatre legend was a last minute replacement for the Dawson's Creek actor - who is battling stage 3 colorectal cancer - at the cast reunion event on Monday (22.09.25) as the 48-year-old star was battling "two stomach viruses".
In an Instagram post reflecting on the emotional charity event, Lin-Manuel revealed how his friend Thomas Kail - who directed Hamilton and is married to Michelle Williams - brought him on board as a last minute favour.
He wrote: "Kail called over the weekend: @vanderjames caught a virus and was unable to travel to NY for the Dawson’s Creek reunion Monday.
"Now I’m godfather to Tommy and Michelle’s kid, so filling in for Dawson last minute falls under general coverage."
He described being part of the event as an "immense privilege", while comparing the entire situation to "an episode of Quantum Leap".
He added: "what happened next was for me, more like being in an episode of Quantum Leap;
"I had the immense privilege of being present as an understudy so that people's love for James, his family, and this incredible cast and show could reverberate all round the Rodgers and the world."
The Mary Poppins Returns actor also revealed how he was sending photos and videos to James during rehearsals and the show itself.
Michelle was reunited with castmates Katie Holmes and Joshua Jackson at the event, while James - who portrayed Dawson Leery in the show - had to pull out of the live reading of the pilot episode in aid of the F Cancer charity, but he still appeared as a surprise via a video.
He wrote on Instagram: "This is the evening I’d been looking forward to MOST since my angel Michelle Williams said she was putting it together, way back in January ...
"So you can imagine how gutted I was when two stomach viruses conspired to knock me out of commission and keep me grounded at the worst possible moment.
"Despite every effort ... I won’t get to be there.
"I won’t get to stand on that stage and thank every soul in the theatre for showing up for me, and against cancer, when I needed it most."
