If you're going to be in Ice Skates buying guide for detailed information about buying hockey ice skates, including sizing.
Skate Construction
You will notice that goalie skates have boots with very low ankles. You might also see that the blade is different from that on a regular hockey skate. They are flatter and wider to facilitate quicker side to side movements and easier directional changes. Something you won't be able to see, but which you can certainly feel, is the extra padding and reinforced construction to help protect the feet from flying pucks.
Buying for Young Goalies
One of the most important things to remember when buying skates for children is that, yes, their feet are growing. However, that doesn't mean that you should buy them skates which are so big that they are swimming inside their boots. The purpose of buying the right size skates is to optimize the skater's comfort and safety. The boot should fit snugly and have plenty of ankle support. If a child tries on boots and you see their ankles leaning inwards, then they need a different size.
If you are outfitting a child goalie with all the necessary equipment, no doubt you will be wondering what all of this will cost you. Be sure not to sacrifice quality for cost, as much as a cheap pair of skates might be appealing. You want the child to be comfortable so as to not drop out of the sport by mid-season due to poorly fitting skates.
Very young kids don't really need special goalie skates until they are able to wear either a size one or two. Then they will require junior goalie skates.
