thegreatape +1
I have 2 westies, both are very fit and have no skin problems etc. Although 1 is quite a bit faster than the other, they both seem to have the “attitude” of younger dogs.
They are both very friendly with people, however, 1 of them does not like children at all. He is very wary of them and does not like any attention from them at all, whereas the other is fine. The wary one once showed aggression to my friends daughter, didn’t actually nip her but certainly would of if he was allowed to continue. He was suitably “instructed” and has never done it again but I do not trust him around children.
As both dogs are from the same stock and have been trained and handled in the same way, it comes down to their individual personalties.