Birkenstock sizing for girls - help please!

[miaowmix]

Hello, I am about to order some (bargainous) Birkenstock Rio sandals for my DD for next summer, and am getting myself in a muddle about sizing. Is it right that you should size down? I am trying to figure out what size she will be in a year, based on her being a 29 (11/12 I think) at the moment. Any help gratefully received as these sandals are about to sell out!
Thanks in advance

hopeful bump

Anyone?
(shameless and desperate bump)

I didn't order a size down for birkenstocks for dd and they fit her fine, and possibly will do another summer.

Oh thanks for replying Cat, I think I'll just do the size I think she'll be in summer then.

They're on Amazon btw and it's a v good deal in certain colours/sizes

We will probably just let out the toe strap to make them do at least half of another summer.