Who knew a Malfoy family reunion could be so sweet?
The two actors posted adorable shots on Instagram from the afternoon, with the 59-year-old Isaacs beaming about his onscreen son in his caption.
"So proud and, along with the audience, thrilled to see my boy commanding the stage today, breaking hearts and filling pants," he wrote. "Equally terrifying, he's recording music and has a book coming out too. I feel smug if I take the bins out on the right day (doesn't happen often). I'd hate him if I didn't love him."
Isaacs jokingly added about his complexion, "That's a work tan btw. I haven't caught trumphilis."
The 34-year-old Felton also posted a sweet selfie of the two. "My father heard about this play I was in @222aghoststory," he captioned the moment.
Felton played Draco Malfoy to Isaacs' wicked Lucius Malfoy in all eight of the Harry Potter films, starting with 2001's Harry Potter and the Sorcerer's Stone.
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The iconic Potter father and son duo previously appeared together for this year's HBO Max special, Harry Potter 20th Anniversary: Return to Hogwarts.
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"I was asked to be on that, and I decided I didn't want to do it," she told Virgin Radio Saturday host Graham Norton, via a clip uploaded to YouTube. "I thought it was about the films more than the books, quite rightly. That was what the anniversary was about."
"No one said don't [do it] ... I was asked to do it and I decided not to," the author added.
Rowling, 57, came under fire in June 2020 when she appeared to support anti-transgender sentiments in a series of tweets. Though she denied that her views on feminism are transphobic, she doubled down on her controversial standpoints in a lengthy essay shared on her website days later.