A cause of death has yet to be revealed, but former band mate Jack Casady said Anderson had recently been entered into hospice care. Kantner died of multiple organ failure and septic shock.
Anderson was born Signe Toly in Seattle, and raised in Portland. She joined Jefferson Airplane in 1965, marrying Merry Prankster Jerry Anderson shortly after.
The vocalist sang on the band's debut LP in 1965, "Jefferson Airplane Takes Off," which featured her lead vocals on Chet Powers' "Let's Get Together" and "Chauffeur Blues."
Look back at old photos of the band:
Anderson decided to leave the band in 1966 after giving birth to her first child. She stuck with Jefferson Airplane as it searched for a replacement, which would become Grace Slick of Great Society.
Anderson gave her last performance with Jefferson Airplane on Oct. 15, 1966. Slick took the stage with the band the following night.
After news came out of her death, tributes from Anderson's former band mates poured out on social media.
"One sweet lady has passed on," Marty Balin wrote on his Facebook. "I imagine that she and Paul woke up in heaven and said 'Hey what are you doing here? Let's start a band' and no sooner then said Spencer was there joining in!" Balin was referring to Jefferson Airplane's late drummer, Spencer Dryen.
SIGNE"One sweet Lady has passed on. I imagine that she and Paul woke up in heaven and said "Hey what are you doing...
"Signe was one of the strongest people I have ever met," guitarist Jorma Kaukonen wrote on his blog. "She was our den mother in the early days of the Airplane... a voice of reason on more occasions than one... an important member of our dysfunctional little family. I always looked forward to seeing her when we played the Aladdin in Portland. She never complained and was always a joy."
"I was just informed of the passing of Signe Anderson, the same day as we lost Paul," bassist Casady wrote on Facebook. "Signe was our, Jefferson Airplane's, first female singer. I had been in touch with Signe this past week as she had moved from her home to hospice care. She was a real sweetheart with a terrific contralto voice coming from a solid folk background. Listen to how she made the three part harmonies of JA Takes Off (first album) sound so thick...her wonderful tone between Paul's and Marty's. A sad day... for those of us still here."
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