Is the correct way dds or dd's?

[JustPoppedIn]

The sentence is 'dds first holiday', with or without the apostrophe?

With apostrophe as the holiday belongs to dd and the apostrophe indicates possession:

if 1 dd then "dd's 1st hol"
if more than 1 then "dds' 1st hol"

Oh a bit like they're and their then? Where
their shows possession and they're is plual

With apostrophe - dd's - in this case. Unless of course there is more than one DD where it would be DDs'.

However, it is DC not DCs or DC's as children is already a plural

I thank you!

Unless it was the DC's first holiday...

(In which case there would be an apostrophe)

Ok - I'll allow that one vic