[Opinions] Re: If you had a twin...
Perhaps Elizabeth Cassandra or Pericles Charles. My father would have insisted that the boy be named after him, according to Greek tradition. Meanwhile, since I already have his mother's name (the Greek tradition for the first born daughter), he might have chosen to name the other daughter after his beloved departed sister, Elizabeth. Cassandra is the name my mum wanted to give to me, and Charles is her father's middle name.
Actually, I have a pair of cousins from the paternal side who are twins. One has my name, the other is Elizabeth.