ARI SHAPIRO, HOST:

Robina Asti loved to fly. She was a World War II pilot who, last year at 99 years old, became the world's oldest flight instructor.

AILSA CHANG, HOST:

In the 1970s, she began her transition and has lived as a woman ever since. She was especially close to her grandson, Erik Hummel.

ERIK HUMMEL: Robina was just such a great life coach. And as Robina would say, she's seen it all. And she really had. She had been through a World War. She had been through a depression, through a pandemic. And I think she just had so much knowledge to give and share.

SHAPIRO: In 2012, after the death of her longtime sweetheart, Norwood Patten, Robina applied for Social Security survivor benefits only to have them denied a year later.

KAREN LOEWY: They were suggesting that her marriage was somehow not valid because she was legally male at the time of her wedding.

SHAPIRO: Karen Loewy was one of Robina's lawyers in a landmark case against the Social Security Administration. And on February 14, 2014...

LOEWY: Robina, as she would say, received a Valentine's Day gift from Norwood and saw that the money was in her account, and she had finally received the benefits that she should have been entitled to from the day that she applied.

CHANG: It wasn't just a victory for Robina, it set a precedent for all transgender people.

LOEWY: Rather than treating every application from a transgender surviving spouse as somehow suspect, the agency changed its approach to one of presumed legitimacy.

CHANG: A few years later, Erik and Robina would start Cloud Dancers, a wish fulfillment program focused on older transgender people.

HUMMEL: She had a lot of close friends who were transgender that unfortunately committed suicide. And I think that a culmination of those experiences over her life, she really kind of would express to me that one of the things that she wants to do with the remaining part of her life as she lived was she wanted to, you know, make invisible people feel visible.

SHAPIRO: Erik also remembers his grandmother as a roommate. They lived together in New York City for six years.

HUMMEL: That's really one of my favorite memories, just seeing her waving goodbye to me as I went off to work and wishing me a good day. And to really feel that support and to feel the love, I will always cherish that memory.

SHAPIRO: Robina Asti died on March 12. She would have turned 100 next week.

(SOUNDBITE OF BRUCE BRUBAKER'S "OPENING") Transcript provided by NPR, Copyright NPR.