Research the siblings of your grandparents. You might find information that you've been looking for. Or research the siblings of your great grandparents. You never know where you're going to find that ancestor. I found an ancestor on the census that I didn't know was there. I had searched for my husband's great grandmother's family and I found them - all of course with the same surname. When I was looking for information about them, I found his great-grandmother's will. She named her two daughters as administrators. One was his (my husband's) grandmother and the other was her sister. Both were listed with the married surnames. Then I went back to the last census that I had for them and discovered that the sister lived next to them. I just had not connected her because of her last name.