Hello! describes the shoes as "Start-rite" and said they "have the same bar strap, rounded edges, beige sole and round buckle." Hello! also noted that the shoes on Charlotte look scuffed, which could indicate the shoes are aged.
The site said "it's not uncommon for royals to reuse clothing and keep traditional pieces for future generations." George has worn clothes his father wore as a child in the past, such as wearing the same white shirt and blue shorts to Trooping the Colour last year.