The weirdest thing was that when I got married (my twin wasn't) and my surname changed to Hamilton my twin was occasionally heard calling herself Alison Hamilton. And admittedly once I became used to my new surname I occasionally said Lorna and Alison Hamilton.
Wow, I find that rather fascinating. I'm always wondering how things will go once my girls are old enough to not spend virtually every waking moment together. One funny thing in their speech about each other is that they have always used the expression "me girls" rather than "we girls" or "us girls" when referring to themselves in the plural. I never bothered to correct when they were younger, figuring they'd just outgrow it, but they're 13 now, and that is the one "twin-speak" they still use. I'm pretty sure they know it's not the way other people talk, but I think that's how they genuinely see themselves as a pair; that is, they are "me" and not "we".
After 13 years, I'm still fascinated by the whole concept of identical genes in separate bodies. And, oh yeah, they don't have matching names: Sarah & Jessica.

Maria