The 59-year-old actress paid tribute to Alexis in a series of tweets Tuesday on the second anniversary of her sibling's death.
Rosanna shared a throwback photo of herself with Alexis in a car. The picture shows Rosanna smiling at her sister as Alexis gives a grin.
"2 years ago today. Alexis Arquette left this planet we love you Alexis," Rosanna wrote.
Alexis was an actress who appeared in such films as Last Exit to Brooklyn, Pulp Fiction and The Wedding Singer. She died at age 47 in 2016 of a heart attack stemming from complications from HIV.
Alexis' other sister, Patricia Arquette, spoke out in 2017 after Alexis was left out of the Oscars In Memoriam reel. She said Alexis should have been included in the tribute due to her work as an actress and a transgender activist.
"It's really unfortunate that the Oscars decided they couldn't show a trans person who was such an important person in this community. Because -- trans kids -- it could have meant a lot to them," the star said.
Alexis was sister to Rosanna, Patricia, David Arquette and Richmond Arquette. David honored the actress in March 2017 by naming his second son Augustus Alexis.
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