'Supergirl' season 3 spoilers, news: Chyler Leigh talks Alex and Maggie's wedding; Alura recast

Alex and Kara Danvers sit side by side in a "Supergirl" promo still.The CW

Wedding bells are ringing for "Supergirl" couple Alex and Maggie this season 3, and actress Chyler Leigh has opened up about what fans can expect from the newly-engaged couple.

Leigh plays Alex Danvers, who proposed to girlfriend Maggie Sawyer (Floriana Lima) at the end of season 2. The scene ended with Maggie smiling at her beau, although it was not revealed if she said yes.

"When we come back, they're in the process of planning the wedding," Leigh told Entertainment Weekly.

While the couple is surely excited for the upcoming nuptials, Alex may not be enjoying the wedding planning as much as she could.

"It becomes quite an uncomfortable position for Alex, because obviously when you're planning a wedding, you're talking about inviting family," Leigh added. "And one of the most important people to her is her dad, and he's not going to be there. So for her it's bittersweet."

Alex is not the only one with daddy issues this season, as "Supergirl" executive producer Andrew Kreisberg said that Maggie's father will also be a potential problem in season 3.

"Episode 3 is all about Maggie and her dad," Kreisberg said, calling the episode some of the "most heartbreaking stuff" he has ever done.

Carlos Bernard is set to play Maggie's father this season.

Speaking of parents, Kara Danvers' (Melissa Benoist) mother Alura will be making more of an appearance this season. Erica Durance from "Smallville" will fill in for Laura Benanti, who played mom to Supergirl in the first two seasons.

"Supergirl" season 3's overarching theme centers on self-discovery, as Kara struggles with juggling two different identities: herself as a human and as a Kryptonian. Supergirl will be going through a tough spell as she deals with the loss of her lover, Mon-El (Chris Wood).

"Supergirl" season 3 airs Mondays at 8 p.m. EDT on The CW.