Upvote:2
Your extension on I-94 allows you to remain in the USA. I believe when you leave the USA, your I-94 will get an exit stamp. When you leave the USA your I-94 is over, unless it is a short-trip (up to 30 days) to Mexico, Canada or adjacent islands, in that case they will re-validate your existing I-94.
Leaving the USA for any other country, like India will result in your I-94 showing an exit stamp. When you return they will have to issue you a new one, however you will need to have a valid visa to get one.
Without a valid visa they probably won't issue you a new I-94, and on the Indian side you probably won't be allowed to board the flight.
Your son will be allowed to re-enter as he should be a USA citizen by birth (you may need documentation to prove that). Your wife will not be allowed back in without the appropriate visa.