In the middle of a brilliant family day out, junior doesn't make it to the bathroom in time or baby needs a new nappy and you forgot to bring your changing bag.

All you can do is head home early with a very disappointed family!

However, some parents in America are starting to help each other by leaving spare pants, wipes and nappies in baby changing rooms. 

One woman found a package in a local store this week. 

What a fantastic idea.

I hope it catches on...