I have been searching for my Fathers father for many years. My Father was born in 1893 in Dundee Scotland. His name was David Milne Gardner. He was 3 years old when his Mother became pregnant again, this time she married. But my Father was not brought up with the family. On his birth certificate it just has his Mothers name Maggie Gardner. She was not poor and was well educated. My question is could it be possible that my Fathers father was also the father of the rest of the children 5 in all. With DNA being very popular would it be possible for me to find out through DNA if her husband was my Fathers father. Which members of the family would have to give samples. I really dont know how it works. I am close to one of my half cousins but none of the rest of the family.