This was provided by Mary Ann Blood (Sydney's Sister):

Sydney (January 29, 1943 - May 9, 2017) passed away unexpectedly in her sleep due to natural causes at the age of 74. The coroner said that 60 years of smoking probably was the main cause of her death.

No autopsy was performed.

She had a great life! She got married for the first and only time on December 15, 1984. She and her husband, Ron, did many fun things together including travelling, camping and going to Las Vegas. They didn't have any children together, but he had four children from a previous marriage. Sydney had four step-children and numerous grandchildren and great-grandchildren and two great-great-grandchildren who all adored her so she was very content. :)

She and I were very close. I will miss her forever.

Note: Sydney and her family left Bothell in 1959. She graduated from Verdugo High School in Tujunga, CA, in June of 1961.