Mine will be 4 years apart, so probably not.
My twin nieces do (2 yrs old), but do so begrudingly. They are hilarious about what they wear. They share a closet, but I swear they remember "who bought what for whom". I love hearing them bicker over it in the mornings when we visit- makes me laugh and reminds me of the way their mom and I used to fight over clothes!
In my house growing up... three girls... yup, we shared. The rule, though, was that you had to ask the "owner" first. My younger sister was notorious for showing up at a school function or practice wearing something of mine knowing full well I wouldn't say a word to her in public. At home... not the case! As we got older, our shapes changed and we can't really share anymore, but it was fun in HS to have double the wardrobe!