Your child flushed a toy down the toilet and it caused the toilet from the downstairs apartment to clog and flood are you responsible?

Yes. I know it's difficult to keep an eye on your children every minute of every day. But the fact remains, a child obviously cannot be held financially responsible for causing damage to someone else's property. So the burden falls to you. It's your child, so it's your responsibility, regardless of how attentive or inattentive a parent you are.

I mean, it's certainly not your downstairs neighbors who are responsible for the damage! You can say "it's not my fault, my kid did it" all you want, but that argument falls apart when you consider that you are expecting your neighbors to pay for the damage done by some kid they don't even know.