If you want to learn more about training and controlling your Jack Russell, my ebook is bound to save you hours of training trial and error and relieve a lot of stress from the process: The Jack Russell Lover's Ultimate Guide to Training comes complete with a full chapter on mix breeds.
My 11 month old Male Jack doesn't like peeing in wet grass
My 11 month old male JRT has taken a massive step backwards with toilet training.
He was perfectly trained very early on, but when we moved house and my other female JRT got cystitis and wee'd on the floor, it all started going downhill.
He peed on the floor a couple of times and now he seems to prefer that cold tiled surface. We've had to block off the downstairs area which is where he is doing it. He will even break down the barrier to get down there!
This morning he picked his way through the wet grass (wet from rain or dew) and climbed into a plant pot so his feet wouldn't touch the wet.
We have gone back to treat training for doing his business outside, but he seems to be paranoid about wha surface he prefers to go on.