Glee’s Kurt and Blaine are about to get some interesting friends!

Oscar winner Patty Duke and Family Ties‘ Meredith Baxter (a newly out lesbian) are joining Glee as a longtime firmly committed lesbian couple who have been together for 25 years, sources confirm exclusively to E! News. We’ll first see them in the season finale, shooting next week, and both Duke and Baxter will stay on as part of the Glee family, returning next season as recurring characters. We’re told Duke and Baxter were the first choice for these roles and immediately said yes.

And speaking of question popping…AHEM.

Their storyline involes a whopper of a fan-favorite-couple spoiler, so read only if you really want to know!

According to sources, in Glee’s season finale, Blaine (Darren Criss) decides he wants to propose to on-off boyfriend Kurt (Chris Colfer).

(We’ll pause while you Klaine fans bounce off the walls but please make sure there are no sharp edges.)

Blaine goes to a jewelry store to buy a ring and meet’s Duke’s character, who is the jewelry salesperson. She speaks to Blaine and his love for Kurt, and then she and her longtime girlfriend (Baxter) offer to be their mentors—a couple who can tell them about what it used to be like, and how great it is for this new generation.

The insipration for this storyline was the recent Supreme Court case regarding same-sex marriages, and one Glee source describes the storyline is “topical and sweet.”

Who’s excited?