My family and I have been living in the USA for a long time. Back in 1984, I filled out a re-entry permit form from my sister’s place in Chicago, but I never received the permit. Also, my children got their Green Cards in 1996, listed as minors on their mother’s documents. They are adults now, and according to the law, their Green Cards should be activated.

The re-entry permit you mention from 1984 would likely have expired, and it’s unclear if its absence affects your current status. Your children’s Green Cards, obtained in 1996 as minors, are likely still valid and can be activated with proper documentation and procedures. You should consult with an immigration attorney to clarify your specific situation and advise on the necessary steps.