Buffy Summers and Willow Rosenberg were among the best friends on television during the seven-season run of the cult Joss Whedon television show "Buffy the Vampire Slayer," and the latest Alyson Hannigan 2015 pics show that the two actresses who played them still keep in touch!

While Sarah Michelle Gellar has kept working (most recently in the short-lived sitcom "The Crazy Ones" co-starring Robin Williams as her father), there's no doubt that it's been Alyson Hannigan 2015 that has seen the most success out of the two vampire-slaying stars, as the famous redhead was part of another cultural television smash, "How I Met Your Mother," until spring 2014.

Now, according to Entertainment Weekly, Gellar's Instagram account bears witness to an Alyson Hannigan 2015 reunion that's set to drive fans of the show co-starring David Boreanaz, as the two talented actresses cozy up to each other in a few adorable snaps!

The Mary Sue reports that the Alyson Hannigan 2015 reunion came on the anniversary of the last episode of "Buffy the Vampire Slayer," the series that turned both actresses into superstars - and Alyson and Sarah Michelle were more than happy to celebrate the 12-year anniversary of the beloved show!

People Magazine reports that the Alyson Hannigan 2015 was apparently a very family-oriented affair, as by the look of it the two actresses were hanging out at the birthday party of one of Alyson's children, her now three year-old daughter Keeva Jane Denisof.

It's unclear whether there were other celebrity babies around besides Sarah Michelle's, but it wouldn't be surprising to know that Hannigan's "How I Met Your Mother" co-stars with children, namely Neil Patrick Harris and Marvel actress Cobie Smulders, were also around with their husbands and children for the adorable-looking children's party.

In any case, the Sarah Michelle Gellar and Alyson Hannigan 2015 reunion pics went viral, and there's no doubt that there are more than a few remaining fans of the show out there!