Snakes N Adders - True, although the zip up the back can make them a little tricky to do up so if you're between size up.
Rook N Roll - I found these a little narrow, so if you're between size up.
Topsy Turvy - True to size, the zip up the heel just makes them a little tricky to do up. Again, if you're between sizes then size up!
Colour It In - Perfectly true to size, no need to size up
Chalk It Up - Perfectly true to size, I had sock room too.
Pipsqueak - True to size!
Good boy - A little generous but if you want to wear thick socks stick to you normal size.