My sister asked a relative, while we were walking towards the house were the funeral took place, it turned out that she was in a coma for over four months right after the death of her father-in-law.
The worst thing, that no one told us about her condition, some people might have presumed that we knew from others. It's also our mistake that we don't ask or visit people as we didn't maintain family ties, so we can't blame anyone for that.
It was just sad that I knew her, how sweet person she was, with beautiful smile in her face. God bless her soul, and have safe transition to judgment day. What ever she has done good deeds takes her straight to paradise on a judgment day.