Sam's ankles over-pronate. It's was too hard to keep him still to get a picture, but it looks something like this....
...basically, they curve in dramatically and it can make walking, running and balancing very difficult. It also stretches out the tendons. We noticed this when he starting standing.
Here are the little braces that Sam has to wear now. He wore them for 2 hours the first day and as long as his feet don't show any irritation he can increase one hour a day until he is wearing them all day (except for sleeping, of course).
Here they are in his shoes. These will work for 2 shoe sizes and then we'll have to get new ones.
He doesn't mind them too much. I think as long as we increase the time slowly he'll get used to them. I think the hard part is having to wear socks and shoes in the house and his feet get all sweaty.
As soon as he put them on we noticed that he walks with his legs closer together, which is a good thing. He was spreading them apart for balance.
Hopefully, in 6 months to a year he won't have to wear them anymore.