I'm thinking of spending child support meant for one child on all my kids
Are you serious? Why would you spend your child support money this way?
The child support is so low. I need to support all my kids.
It's good to help all your kids out, regardless of who the money was meant for. Sometimes you just need to move money around to cover all your children's expenses. Make sure you have some incoming that'll be able to make up for you dipping into their child support when the time comes.
I'm gonna do it anyway.
In the end it's up to you, I would just be careful not to stretch your money too thin.