@tattedese - this issue of dependents can get quite complex in situations like yours. and all the back and forth won't end your anxiety quickly.... so here is a better idea:
use the IRS dependent tool to determine who can claim whom. Run through it for yourself. And then do it again playing the role of the baby's mother and then the baby's father.
https://www.irs.gov/help/ita/whom-may-i-claim-as-a-dependent
you'll have the truth in front of you, you can play 'what ifs' in answering the questions....and you will have 'ammunition' in any discussion with family members.
