How on earth can you have parents born the exact same years as someone else’s parents?  1904 and 1925?

Found out today my grandfather, Theodore, was born March 25, 1861.  But he didn’t die when Daddy was two as I thought; he died in 1912–when Daddy was eight, the same age I was when I lost my father.  You know, I like the name Theodora for a girl.