My big dog used to be really chill and friendly, my friend who is a dog behaviouralist told me he's one of the few "normal" dogs she's met. I still get comments on how well behaved he is when he's calmly sitting next to me while I'm huddled under a tree or somewhere else out of the way furiously playing Ingress or Pokemon Go, but he's now dog aggressive thanks to some dog that was roaming around at night that decided to randomly attack our small dog while my partner was walking both of them >_< It's really hard work making an aggressive dog not-aggressive again!
My small dog has to stay on a leash for exactly the same reason as yours, also mine is probably going deaf in his old age but has had "selective hearing" since we got him XD
That park looks like a really nice place to hang out, no wonder the guy and his dog and you all like to walk through/hang there :) This piece is so relaxing and idyllic.
Awwww that sucks so bad that your dog's excellent behaviour is ruined >_<.
It's funny but I only realise it after I have my own dogs, they have their own temperament and no matter how often I bring them around to walk outside, it doesn't feel like their behaviour can improve significantly. Though I do notice that they become less secure when I haven't walked them in a few days because
I'm lazythe weather is too cold so it's always good to walk often with them.Thanks for letting me know more about your dogs, fyn :).