James McAvoy's son was furious with him when he had his photo taken with Taylor Swift.

The 36-year-old actor and his wife Anne-Marie Duff have five-year-old son Brendan together and father and son have bonded over a shared love of the country-turned-pop star. Unfortunately this led to problems when James was lucky enough to meet her.

"My kid and I listen to Taylor Swift's last album all the time," he explained to ET.

"When I got a picture of us together and sent it to my kid, he wasn't even excited. He was just angry with me."

The pair's favourite Taylor album is her latest offering 1989, which saw her move away from country music to a more traditional chart vibe.

James was speaking at the Comic-Con event in San Diego over the weekend, where he was promoting his upcoming movie Victor Frankenstein. It tells the iconic story from hunchback assistant Igor's point of view, with Daniel Radcliffe co-starring.

He was on hand to answer some questions along with James, with the guys fixated on one particular part of the shoot: their hair. Both had to wear long extensions to get into character and they found them hard to handle.

"I don't know how anyone deals with them. The stress, you have to wash them! If you don't, they get really rank,” Daniel explained. “You have to wash them in a very delicate way, because otherwise, they're all going to fall out."

James concurred, revealing he found shower trips particularly stressful at the time.

"One [hair-extension] comes out and you're like [gasp!]” he explained. “I had that a couple times."

The Scottish star doesn't have to worry about that anymore as he's currently sporting a closely-cropped head of hair for his upcoming flick X-Men: Apocalypse.