In a new deleted scene from the Season 3 Blu-ray/DVD, exclusively revealed below, Kara Zor-El (Melissa Benoist) shares a quiet moment with Samantha Arias's adoptive mother, Patricia Arias (Betty Buckley). Kara warns her that Reign is on her way, looking for Patricia's granddaughter Ruby (Emma Tremblay), and reveals that a safe room has been prepared in the basement.
Arias begins to cry, talking about how she thought she'd never have anyone else in her life after the death of her husband. Then, Sam arrived from outer space and Patricia was able to start anew, wanting to ensure that the child never felt like an outsider.
"Ironically, I was the one that sent her away," Patricia says at the end of the clip, which you can watch below:
Reign is basically Supergirl's Doomsday, the product of years of Kryptonian science. On the day of the planet's destruction, she (like Kal-El) was sent to Earth as a baby. Unlike Superman, however, her trip to our planet was part of a plan for her to conquer the place.
Season 3 of Supergirl flies onto Blu-Ray and DVD Tuesday, Sep. 18. Season 4 of the series returns to The CW Sunday, Oct. 14.