Ashton Kutcher turned 36 today, and in honor of Kelso turning one year older, we bring you some Ashton Kutcher fun facts, as well as a timeline of his relationship with his former That '70s Show co-star Mila Kunis!

E! News is reporting that the "wo and A Half Men co-star (and Charlie Sheen's biggest rival -- yet, like it or not, Ashton's debut performance on the show drew in 28 million viewers, the most viewers at any time of the show!) celebrated his birthday with his lady love. However, if you're expecting a series of photos and press releases to come out showing the couple celebrating and smooching, you're in for a sore shock: Ashton has made a promise to do everything BUT that when it comes to Kunis. "I am going to do everything in my power to have this relationship be private," he said.

Given that the couple's previous high-profile relationships were all over the media -- Ashton, of course, was previously married to Demi Moore; Mila was previously involved with former child star Macaulay Culkin -- it makes sense that these two want to keep their situation on the down-low!

Kutcher and Kunis met in the mid-90s, of course, on the set of That '70s Show. Ashton was 20 at the time, and Mila was 15 (which explains why they didn't start dating right away!). Believe it or not, though, they EACH gave EACH OTHER their first-ever kiss...on the show! But things seem to be going well for the couple: last December, Ashton attended Mila's brother's wedding with her, and just a few weeks ago, Mila attended Ashton twin brother's wedding with her beau.

Of course, the couple have also met each other's families... and it seems to be all good on that front!

Lest you think that Ashton is too much like his "Kelso" character in real life, you would be wrong: according to the UK division of Comedy Central, Ashton majored in Biochemical Engineering at the University of Iowa. He dropped out to try modelling, and landed a job at Calvin Klein after being spotted up in a talent search.