Dh thinks Erin is short for Catherine?

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Just starting to tentatively draw up lists of names.

Dh comes out with, "I really like Erin, and we could always use Catherine on the birth certificate."

He claims that Erin is a perfectly acceptable diminutive of Catherine, and that he knew a few at school. I think he's making it up/remembering wrong/these Erins played a prank on him.

In my books, Catherine can be shortened to Cathy or Katie, but not to Erin??

... full name so by all means use Erin for Catherine.

This makes no sense. Erin is not a nickname or a shortening. You like erin so why would you need a different name on her birth certificate?

I actually like it more short for Catherine!

I’ve not heard of it being used as such before but I don’t see why not.

It makes far more sense than Peggy being a diminutive of Margaret! Or Sadie as a diminutive of Sarah.

I LOVE Erin. It's the only girls' name on my list. And definitely not as a shortening of C/Katherine!
Must add though, I currently teach an Erin who mistyped her name on a piece of work as 'Erni'. The nickname has now stuck!

He is wrong. Both Catherine and Erin are nice names in their own right.

I think he's really clever! I know a Topher short for Christopher so why not?!

No it’s not a shortening of Catherine.

Weirdly my daughter is called Erin Catherine and I didn’t realise that Erin was hidden inside Catherine until my sister in law pointed it out!

Your DH is full of balloon juice.

Erin is not short for Catherine.

It really isn't. But why not use Erin as a nickname for Catherine (although the pronunciation is a bit different ime)?

But I wouldn't count on other people calling a Catherine Erin.
Would you be upset if people (friends from school etc) called her Cat, Katie etc?

It's not short for Catherine.

Just use Erin if you like the name.

I think referring to her as Erin X will cause problems if her real name is Catherine X.
Thinking official forms/school etc.