I need some information

I need some information about problems or defects in the ankle. My husband had a problem with his feet and ankles when he was a child and had to wear corrective shoes. The problem was that he walked on the inside of his feet. Now our youngest son is kind of walking the same way. Our son’s is not as bad as my husbands but I would like to know what it is called and what I can do for it. I have showed it to our dr. before and they don’t think it is major but I would like to know what I can do. Thank you Melissa