Hello,I don't know of anything geared up specially for birthdays,but,our twins were seven the other year,and we booked a ps at Cinderella's table.While your in MK you can go to the Town Hall,near the entrance and they will give you a birthday badge,which makes their day a little special.The CMs often comment on it when they see someone wearing one.If you book a ps at any Disney restaurant they will add a little something if you tell them there is a birthday.Also the GF does a pirate cruise,where they go hunting for treasure,they really enjoyed that.
Geoff.