The actresses became firm friends on the hugely popular vampire series, and gave Buffy fans a treat when they posed for a selfie together - and we think they've barely changed at all!
Sarah, who played butt-kicking slayer Buffy Summers, looks fresh as a daisy in the snap, taken at a party thrown by Alyson - aka Willow Rosenberg - and her husband Alexis.
Alongside the photos, Sarah paid tribute to her pal's party-throwing expertise with the message: "So this girl (#AlysonHannigan) and her husband (#AlexisDenisof) know how to throw a party.
"I thought I was good with the crafts, till I went to this party #CraftMaster Thanks for having the #PrinzeFamily I've never seen a farm and pony rides in Santa Monica before #NowIveSeenItAll."
She later added: "@alydenisof and @AlexisDenisof Thanks for such an awesome party and my new #Giraffe You are the #CraftMaster."
Mum-of-two Alyson in turn couldn't resist gushing about her gorgeous former co-star, saying: "I had a lovely time with @SarahMGellar when I ran into her at Michaels today. Our mutual love of crafting would make Willow happy I think."
It's been 12 years since the last ever episode of Buffy aired, and Sarah recently paid tribute to her character.
Sharing a montage of pictures from her time on set, she wrote: "12 years ago, I said goodbye to a friend. It was an incredible journey that, I am so incredibly proud of. Thank you all for joining me, and continuing to tell her story #BuffyTheVampireSlayer #BTVS."
Sarah went on to star in films such as The Grudge and Scooby-Doo.
However, she recently admitted that despite 'saving the world' many times on screen, her favourite role is that of mum.
She has two children, Charlotte Grace born in 2009 and Rocky James born in 2012, with her (rather dishy) actor husband Freddie Prinze, Jr.
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