Politically, the only way to make it fly might be to (1)affirm birthright citizenship for those who had it before the law went into effect and (2)to allow children born of foreign parents who were in the country legally to apply for the same right under the 14th amendment as was granted automatically to children of parents who were not in the country legally.
The threat of retroactive revocation of wrongly acquired birthright citizenship could be enough to get the powerful ethnic lobby to agree to no more going forward to get a grandfather clause for those already here.
You still don’t have to allow minors born of illegals before the law goes into effect to stay. Send the parents back and send the minors back with them. You would not want to separate minor children from parents and there is nothing illegal about that. When the child reaches 18 they can apply, with proper and verifiable documentation, for reentry as an adult citizen, without bringing their parents or other family.
Thanks for the explanation.