When Ashton Kutcher and Mila Kunis both got their big break playing lovers on “That ‘70s Show,” the young actors, who are now engaged, didn’t even like each other -- at least that’s what a source told Radar Online Tuesday. The insider said Kutcher and Kunis might be planning a wedding and to possibly have children together now, but when they first met things were quite different.

In fact, they “despised each other” when they were making the hit sitcom. “Everyone shakes their head over the romance,” a longtime friend of Kutcher, 36, and Kunis, 30, said. “Ashton and Mila were absolutely not friends during much of the making of ‘That ’70s Show.’ In fact, they couldn’t stand working together.”

Their onscreen makeouts must have been awkward, if the source’s information is correct. Kunis revealed after the show completed that Kutcher was actually her first kiss. She played the spoiled cheerleader Jackie, who dated Kutcher’s airhead Kelso. The characters' relationship didn’t stand the test of time and the show came to a wrap in 2006 after eight years on the air.

“The two were never close on the set,” the source told Radar Online. “Quite the opposite!”

But things have changed since “That ‘70s Show.” “Everyone’s amazed at how different Ashton and Mila are together from when they were younger,” the source said. “It’s such a total change and now they’re a match made in heaven – something that no one could have ever predicted in their wildest dreams back then!”

Kutcher’s ex-wife Demi Moore was reportedly the catalyst that brought the two together. The “Two and a Half Men” star was accused of cheating on his then-wife, 51, with a younger woman. “Mila was the one who came forward to bury the hatchet,” the source noted.

“She could see Ashton was going through a tough time and reached out to him.  They built a solid friendship, which was a new thing for both of them.” The two were rumored to have begun dating well before Kutcher’s divorce from Moore was finalized, but once the legal proceedings were officially over the two decided to get engaged.

Moore reportedly isn’t happy about her former lover moving on. She was rumored to have sought out Kunis’ number through her daughter so she could call her and tell her Kutcher was a cheater. Neither Moore nor her ex-husband has publicly commented on the alleged phone call.

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