What do Sharon Osbourne and Mila Kunis have in common?

Apart from having famous paramours, not much. However, that all changed yesterday when they pulled off the best April Fools Day pranks among the celebrity set, both of which immediately went viral across the web... at least, we thought both of them pulled it off, but as it turns out, we were fooled.

The nearly two million followers of Mila's fan page on Facebook were duped when a picture was posted of two positive pregnancy tests and a smiley face emoticon.

Mila then seemingly followed up the photo with this joyful post: "As you all probably know, I'm pregnant and I've decided to take the next 9 months off with Ashton Kutcher in Hawaii. Don't worry, my manager will be posting pictures everyday as usual so you can all see the progress and news. :) I'm so happy. Any ideas for the baby's name? I love you all and thank you for the support. :)xx."

However, it turns out that neither of the photos came from Mila and it was a fan-orchestrated hoax. "I got y'all, Mila isn't pregnant! mouhahahaha;) xx," wrote the operator of the fan page.

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Meanwhile, Sharon's prank was undoubtedly her all the way. She turned up to her CBS morning chat show The Talk after a two week vacation with some news that shocked her fellow co-hosts. "I went to an in vitro fertilization clinic and I found a donor with an egg—a beautiful egg because she's a beautiful lady—and put together with Ozzy's sperm, and it was implanted in me and I have to say...I am now pregnant," said Sharon, with tears welling up in her eyes.

The audience gasped and applauded as her fellow co-hosts either hugged Sharon or sat there with jaws dropped. Considering that Sharon turned the big 6-0 last October, we're amazed that anyone bought this. But after a few minutes, she finally came clean.

"I have always wanted to get into acting and I just gave an Oscar-winning performance because it was an April Fools' joke and I love you all, goodbye," she said.

Related Article: Sharon Osbourne Quits 'America's Got Talent'

And in what was likely an April Fools' Day prank that missed the boat by more two hours, Lindsay Lohan also attempted to follow Mila and Sharon's lead. "It's official. Pregnant...," she tweeted. The only problem was that she wrote it at 2:30 a.m. on April 2 from Sao Paulo, where she is currently staying for a few days of R&R.

Nice try, Linds.

Which do you think was the best April Fools' Day prank?

Photos courtesy of Getty Images and Facebook