No matter what worries you may have about the world we now live in, at least we can all take comfort in the knowledge that Sarah Michelle Gellar and Freddie Prinze Jr still love each other and are very happy together after 15 years of marriage - which is about 40 in Hollywood years.

The pair were up there with Britney and Justin as the ultimate nineties couple, having met on the set of I Know What You Did Last Summer, although it wasn't until two years later that they got together. Freddie Prinze Junior told E! News in an interview earlier in the year why he believes they are still going strong:

"We were just friends. That's one of the reasons I think our relationship has always been so good. We were just friends for a good two years before we ever went on a date. She knew what kind of guy I was. She knew what my morals were, what my priorities were and vice versa. We already kind of knew all the faults in the other person."

He added, "We ended up being the perfect balance. But it didn't happen until years after and there was a solid foundation built, and that's probably the main reason why we've always been cool and groovy."

Check out how "cool and groovy" they are below in the adorable montage Sarah Michelle Gellar posted on Instagram to mark their 15th wedding anniversary yesterday, which she captioned with: "My husband thinks I'm crazy, but I'm not the one who married me. #happyanniversary @realfreddieprinze 15 years!!"



My husband thinks I'm crazy, but I'm not the one who married me. #happyanniversary @realfreddieprinze 15 years!!

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