When it rains, it pours

Why is it that when one dog gets injured, everyone else has a new trauma as well. I just finished giving antibiotics and pain killers to my aussie for a limp. They took x-rays and they were not completely conclusive, but we treated him anyway based on what could have been wrong. The middle bone in his 'wrist' looked slightly out of place. That was the only cause they could find. He was just sleeping and when he got up he was limping and it got worse as the night wore on. He kept me up half the night with his restless sleeping. Now my 8 month husky/border collie has taken to screaming uncontrollably when you touch her spine along with uncontrollable intermittent diarrhea. Poor girl is only 8 months old! She acts fine and everything is normal, but if you even get caught trying to touch her spine, she screams and runs. And that's not even it! My 1 year old Boston terrier/MUTT decided it would be huge fun to play with a broken clay pot that had just blown off into the lawn after a huge storm this afternoon and sliced his paw wide open. A good 1/2 inch deep slice covering most of his pad. It's a regular blood bath. Now I am just waiting to see what the Shiba Inu will come up with. He's the only one without ailments for now.