Kate Upton too young for new boyfriend?

October 6th, 2013 6:20pm EDT

Kate Upton Kate Upton's new boyfriend was initially reluctant to date her.

Former 'Dancing With the Stars' professional Maksim Chmerkovskiy, 33, reportedly feared the 21-year-old model was too young for him but fell in love with her after they became close friends.

A source told People magazine: "(He was) hesitant to start things with Upton because she was so young."

But the insider added: "They have a lot of fun. She's very mature for 21."

The couple started dating after being introduced by mutual friends six months ago.

The source said: "Along the way, it turned into something else. They just clicked. They are very serious. They have a lot of chemistry."

The couple were photographed looking relaxed and happy as they strolled through New York's West Village hand-in-hand last month just weeks after Kate insisted they were "just good friends".

Kate, who insisted last month that she doesn't "put relationships as a priority", recently finished filming her first major film role in New York alongside Cameron Diaz and Leslie Mann in 'The Other Woman.'

Related: Kate Upton, Maksim Chmerkovskiy, Celebrity

Photo Credits: © WENN

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