We all fell in love with Lizzie McGuire's younger annoying brother Matt for his hilarious schemes and quick wit.
But now, 21 years since the show aired, actor Jake Thomas looks completely different from the spiky-haired kid we saw on our screens.
Fans who have stumbled across the actor's TikTok have been stunned to discover it is little Matt all grown up, with many not recognising him at all.
Jake has established a TikTok following of more than 400,000 people, and often posts throwback videos of him as a young kid.
On his latest videos, fans have been questioning whether Jake is in fact the annoying little brother from Lizzie Mcguire.
"Is that Matt McGuire from Lizzie McGuire I’m screaming ... my childhood," one commented.
"What a glow up," another said.
'Omg! I didn’t recognise you! You’re so grown up now!" a fan added.
In one video, Jake is watching his younger self being interviewed, with some fans not even realising they were the same person.
"I thought dude on the bottom was just a random guy watching the video. I HAD NO IDEA THEY WERE ONE IN THE SAME!' one said.
"I refuse to believe that the person on the video actually played Matt..." another commented.
'It took me way too long to realise he’s the kid in this video," a third added.
The now 32-year-old has largely stayed out of the limelight since Lizzie Mcguire ended. He was set to appear in the reboot of the show before it was cancelled in 2020.
He has had some small acting roles since starring in the Lizzie Mcguire Movie in 2003, appearing in an episode of Without A Trace, ER, Cold Case, CSI: Miami and Rules of Engagement.
Most recently, he starred in an episode of S.W.A.T in 2019.
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