Selma Blair returns to “Dancing With the Stars” to visit her former partner Sasha Farber and Alyson Hannigan

Sasha Farber and Alyson Hannigan invited viewers to be their guest on the Disney 100th anniversary episode of Dancing With the Stars.

Farber's season 31 partner, Selma Blair, took them up on that offer during the pair's rehearsal process. Blair dropped into the rehearsal studio to visit her former dance partner as he practiced his "Be Our Guest" jazz routine with his season 32 partner, Hannigan.

Blair was glowing with excitement, expressing how thrilled she was to be back in the DWTS rehearsal studio. She observed their dance rehearsal and gave Hannigan some advice, namely to remember to breathe while executing their high energy number. Blair explained that catching her breath was often a struggle in her dances last season, but assured Hannigan that Farber is the ideal supportive partner.

Todd Williamson/E! Entertainment/NBC via Getty; VALERIE MACON/AFP via Getty Selma Blair and Alyson Hannigan

Hannigan and Blair have never appeared in a project together, but the actresses share one degree of separation in Sarah Michelle Gellar. Hannigan starred opposite Gellar in Buffy the Vampire Slayer, while Blair had a memorable role (and kiss) in Cruel Intentions with Gellar at the height of their '90s era fame.

Blair was a favorite on DWTS last season before she was forced to bow out due to challenges with her health and advice from her doctor. The actress has become an advocate for those with chronic illness since revealing her MS diagnosis. Her stint on DWTS inspired audiences, but MRIs revealed damage to her bones as a result of her dancing.

"The reality is sometimes when you come into things with a chronic illness or a history of a health thing," she told EW at the time. "Sometimes you just really have to take care of yourself and it's not all possible."

Blair championed Farber throughout their time together on the show, singing the praises of his support as a dance partner. "Sasha, I could not have found anyone that could've allowed me to move and accept myself and keep supporting myself," she told her partner. "But to have someone like you to show the world there are partners you can find — there are partners if you let them know you need someone to hold your flailing hand."

Hannigan has found a similar helping hand in Farber, particularly on Motown night when a migraine and resulting nausea nearly kept her from the dance floor. This week the duo landed near the bottom with a score of 18 from the judges for their jazz dance to the Beauty and the Beast track.

Dancing With the Stars airs Tuesdays at 8 p.m. ET/PT on ABC and Disney+, and streams the following day on Hulu.

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