^no, it’s not.
Universities that don’t meet need don’t consider sending a second child to college “a choice”.
Universities that don’t meet need do not consider other siblings. Period. They don’t meet need so your need doesn’t matter to them.
What matters to them is what the student, your child, brings to the college. What the other child’s doing is of no concern to them since your family’s resources were never the primary consideration when they offered FA.
I agree the only way to make them look through it is 1° if you’re nice about it 2° clear that your child can’t stay enrolled at that level of funding. (But you have to be ready to do what you say so tell your child ahead of time that you’re trying this gambit on his behalf. If you really can’t afford it, your child may have to take an unplanned “gap year” to work, with all legal “leave of absence” papers filled so that he can return easily, There’s no saying whether the following year the university will up the package though but at least your child will have $5,500 from a job that can’t really be used against his financial need award but still can help with fees.)
Was child #2 admitted to any “meet need” college?