Sorry, I meant dl.com, not aa.com! Been in both forums today (too much time on my hands today).

PNR: Forgot what it stands for, but often called Record Locator or Reservation Number. Same Itinerary normally means same PNR, but in your case, you would have 2 PNR's, I think. You and your wife in the award one, and your 2 year old with a child's fare and your infant with an infant fare (there are some fees/taxes to pay for the "infant in arms" ticket). The infant probably will be in your adult PNR...

No matter how many PNR's you end up with, they can "link" them so they all show together.

Anyway, you'll need to call in ! Good luck.