Matthew has reflected on his iconic appearance in the 'Harry Potter' films, noting the transformation that began during his ten-year tenure in the popular fantasy series. "Definitely at one point between films two and three, I shot up in height and lost a lot of puppy fat. I wondered if they were going to recast me – we were only contracted two films at a time," Matthew confessed. "It didn’t keep me awake at night, but I considered it a possibility. I’ve since been told there was never any question, but I reckon in some dark room somewhere in California it might have come up."
By 2007, the young boy had grown into a young man. At 18, he attended the UK premiere of 'Harry Potter and the Order of the Phoenix,' showcasing a faint beard and spiky hair.