How I Met Your Dad
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"How I Met Your Dad," the spin-off of "How I Met Your Mother" is slowly taking shape and show executives are in the process of finalizing the cast.

After announcing Greta Gerwig as Sally, a female Peter Pan who does not want to grow up and take responsibilities, "Smash" alum Krysta Rodriguez has been cast in the role of Sally's friend, Juliet.

Juliet, a sexy, flamboyant party-girl, is a successful fashion blogger who is happy that Sally is finally thinking of ditching her "boring" husband.

Drew Tarver will play Todd, Sally's best friend from college and her brother-in-law.

Still to be cast are Todd's husband and Sally's brother, Danny, Juliet's "hot nerd" colleague, Frank, and the narrator.

"How I Met Your Mother" fans are still unsure of a spin-off of their favorite show that chronicles Ted's journey as he sets out to find love. But Gerwig is positive that fans will not be left disappointed.

"How I Met Your Dad" "shares the heart and soul with the original show, so it has the sweetness and the funniness," she told E!News.

When fans are first introduced to Sally, she is already married. But she later leaves her husband and moves in with her gay brother and his husband. While her brother Danny is not pleased at her sharing their flat, Todd is accommodating and loves to hang out with Sally.

Meanwhile, the cast of "How I Met Your Mother" has already extended their support to the spin-off series.

"They're so nice!" Gerwig said. "I went and I hung out with all the cast and they were like, 'If you can be part of this world, it's crazy fun,'" she said. "They told me they believed in me, and it was really sweet."

The pilot is written by "How I Met Your Mother" creators Carter Bays and Craig Thomas, and Emily Spivey. Gerwig also has a major role in scripting the pilot, and said she was eagerly waiting to start filming the show.

"I contributed a lot into the pilot, and I'll be in the writers room staring June 1 if they pick it up," she told E!News. "I shoot the pilot in like two weeks and then hopefully it becomes a real show."