Cute boots.  I purchased these boots in both size 10 & 11 as my boys were wearing size 11 shoes but, rain boots do tend to run large.  I ended up keeping size 10, knowing that they wouldn't last more than a few months as they needed rain boots and I haven't found any brand that fits any differently.  The size 11s were not an option as they were too big - the boots would fly off their feet if they tried to run in them and even keeping the boots on while walking was challenging. We've only had these boots for 4 months and they are already too small!  I'm not sure why rain boots don't come in half sizes to allow some room for growth but, it would make things easier and cheaper as I now need to purchase another pair for fall!