Western twitter, how painful...
There is a 13 YO age min on twitter so anyone that says less than that in their bio can be reported, you can also report for harassment, which will generally side with you as long as you don't literally draw toddlercon.
In fact, you SHOULD. Twitter often goes for whoever reports first and twitter doesn't like these guys just as much as you don't. Do yourself and everyone a favor and don't respond to these guys and just report them.