When I was a girl, my father died. So my greatest fear became losing my mother. I am an only child and we were very close. I used to pray at night and was scared to death if she went shopping and I didn't know when she would be home.
She died when I was 15, from cancer. My greatest fear came true. It was a nightmare but time heals much of the pain and that was 45 years ago and I survived it and went on to have a lovely, wonderful family.
As an adult my great fear was losing a child and thankfully both of my children grew up happy and healthy.