My maiden name is Dolphin, I was also born Karen Dolphin, in Birmingham England in 1975.
I am currently looking into the Dolphin family history. Growing up with a really unusal surname means that I have been pleasantly surprised that there are so many Dolphin's on the record.
My father was born John Dolphin in 1948, his father Herbert in 1918, his father Herbert in 1898 and his father Herbert in 1863. All were born in Birmingham (Aston) and according to the records Herberts father was Thomas born around 1832.
My dad grew up in Aston and we actually live just in the jewerllery quarter less than a kilometer away from where all of my ancestors were born.
I have come across William several times and I am sure that he is a sibling of one of my forefathers.
Once I have researched and had a good look I will hopefully try and email you some information.