[Snow]

I've also got the different sized dog issue, we have a 2 year old female Rottie and 7 mos old male Pug. So far they are great and also love to play/chase each other and there have been no problems as of yet. We do monitor their play and intervene if it looks to be getting too rough (usually they are fine though), but yes I share your worry of unintentional hurt. I'll be interested to see what other members say ...