@Swerd, When she was out because of Health issues affected the court. There has to be some kind of backup? one goes down say sick like she was the last 5 years or more, or like this one her Dying while holding office. She should have retired.
Once again, you should read and listen up on the real news about these things as you seem to be interested.
What happened when Scalia died in Feb 2016? The court had 8 justices.
Senate would not even consider a replacement until 2017 so it was like this for over a year.
Not the first time in history of even numbers or total numbers on the court.
As to her retirement, she was going to retire until the 2016 election results were announced. She didn't miss a day until recently.
