An easy solution is to make it the law that anyone who comes here illegally (adults or children), can never have US voting rights, unless they leave and apply for citizenship through the normal process. Also, do not allow chain migration.
I agree but worry that it might be easy for a lame judge to declare that unconstitutional.
Make illegal immigration a FELONY. Catch them, convict them and deport them. Since they’re felons, no voting rights by definition.
Might be the safest approach to tie a judge’s hands?