Meg, my English Springer is approaching 6yrs old.
For the last 12 -15 months there have been a few occasions when, on returning from her walk, she stops and stares at my Jack Russell and then goes for him in a big way.
Can't see any obvious reason for this but it is getting to be a more frequent occurrence.
Googling suggests "a springer rage syndrome", but I'm not sure. She's great in every other respect and both dogs play and get along fine otherwise.
Any suggestions or experience would be gratefully received.