Hi Lorainne-Murph can be quite 'guardy ' when people knock on the door sometimes he doesn't even raise an ear'ole but other times he runs at it with his 'big bark ' ( especially the new milk woman :rolleyes: )I take him to the door with me and make him sit at my side -but there are still a few times when he will fly to the door barking! ( but this is part of his job ! )
The kids from the school , I hope they get a rollicking -our neighbours son was taunting Muph over the fence a few weeks back ,anyway Murph flew at the fence -he fell off the table he was stood on and I wet myself

:D-but since then he has been barking more at the fence -I explained to the parents and said it might take a while to stop it and they understand .
To be honest if he barks at the door or the fence I don't tell him off as such -I tell him ''enough now '' and praise him for being quiet -he's doing what comes naturally to him -guarding his family
The bull terrier - I don't think tha would change his personality that much - I think it is a combination of him maturing and finding his feet in your household -Murph was attacked by a GSD about a year ago - I posted it on here at the time -I thought it would make him wary -but it didn't
When we got murph we were told -'no rough play ' so we have never done that -if you think about it Sam and hubbie are playing rough-sam growls -hubbie backs off -ahhaa thinks sam ,that gets a reaction -so he might take it a step further next time
He gets plenty of excersise and the kids play football with him ,and finding things but no wrestling or rough stuff
just stay consistant with him - he needs to know what is acceptable and whats not -they soon twig and next week he'll find something else to wind you up with ;) :D
HTH
Liz