'Glee' Enlists Patty Duke, Meredith Baxter as Blaine Preps Proposal

Patty Duke Headshot 2011
Slaven Vlasic/Getty Images

NEW YORK, NY - APRIL 06:  Actress Patty Duke attends the official launch of George Takei and Patty Duke's Social Security Administration Public Service announcements on April 6, 2011 in New York City.

Glee is continuing to champion LGBT equality.

The Fox musical has cast Patty Duke and Meredith Baxter to play a lesbian couple who wind up becoming mentors for Kurt and Blaine, The Hollywood Reporter has confirmed.

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As first reported by E!, Duke and Family Ties alum Baxter -- who recently came out -- personally were recruited to play a longtime lesbian couple who first appear in Glee's upcoming season-four finale.

Blaine (Darren Criss) will encounter Duke's character in the finale, when he decides to propose to on-again, off-again boyfriend Kurt (Chris Colfer). He goes to a jewelry store to buy a ring for his former classmate where he meets the Academy Award winner (1963's The Miracle Worker).

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After she learns of his love for Kurt, she and her partner (Baxter) of 25 years offer to be their mentors -- who will share their journey with them as the couple learn how much society has changed in the past 25 years. The storyline would imply that Blaine could potentially head to New York to join Rachel (Lea Michele), Kurt and Santana (Naya Rivera) on the East Coast after graduation.

E! reports that the storyline was inspired by the current same-sex marriage Supreme Court case. For his part, Glee co-creator Ryan Murphy, who is openly gay, has been a big supporter of President Obama's embrace of marriage equality, hosting a May fundraising dinner for his campaign.

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Baxter and Duke reportedly will return for Glee's fifth season, as deals with producer 20th Television and Fox continue for a formal renewal.

The storyline marks Glee's latest socially relevant one and comes mere days after the Fox musical featured a somewhat controversial school shooting episode. The series long has championed the LGBT community, featuring stories about coming out, bullying and teen suicide.

Baxter and Duke mark the latest guest stars to join Glee this season, with Idina Menzel returning to play Rachel's mother and Katey Sagal poised to play Artie's mother.

Glee airs Thursdays at 9 p.m. on Fox. Hit the comments below with your thoughts on the castings. Are you looking forward to Blaine and Kurt's renewed romance?

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit