Physical Danger
You'll be poked. You'll be pushed, bitten, hit, and your hair will get pulled. You'll be pinched and grabbed, and you'll trip over a lot of little things. And you're in real danger of getting hugged. A lot.
Seriously, you should be strong enough to lift forty to fifty pounds, which weighs a lot more when it's asleep and twice as much when it's swinging its arms and legs around and trying to get out of its clothes.
You must (by law) be up-to-date on your vaccinations, but you'll still be a good candidate for catching whatever your kids have.