My DS2 is 4 and we have the same issues as all of you above, bowel incontinence, fatigue, pain etc DS wears orthotics (hard plastic, half length) which are proving to be difficult to fit in shoes, it's a nightmare isn't it?
Ds's physio recommends Kickers however they are too narrow for DS
at anybody who has the beautiful canvas style boots on the website. We are currently stuck with walking boots, which I have to say, are excellent.
At our last appointment I asked what we could do regarding sandals as DS's ankles are our biggest problem. The dr said to buy a regular pair of sandals, with a closed in back to wear only on days when it is really hot, not ideal but we live up north, summer days are few and far between at the best of times!
I have queried Piedros but the dr said that although they would support the ankle, they would not provide suitable arch support and are not worth the wait/cost when walking boots are more readily available.
I highly recommend the Little Trekkers website, they have a great selection of boots and sandals. Jack Wolfskin also have suitable looking sandals which I'm eyeing up...DH was so chuffed to have sons and therefore quell my shoe shopping addiction...