Although you have a somewhat difficult relationship with your DiL, feeling as you do that she is controlling and manipulates your son, the new baby (if there is one) is definitely news to rejoice over isn’t it?
Others have made very sensible suggestions as to the possible reasons why you haven’t been told about the pregnancy so when/if you are told you must of course react with joy at the news.
A quote for those blessed with a spouse:
Retiring and living frugally in money from downsizing after years of stress
