OP appears to be ignoring any posts that suggests her DH is the absolute root cause of the issues.
Had he started as they meant to carry on years ago by advocating EQUALLY for his wife and both of his children, this would never have happened.
Newborn in ICU - ex won't budge on contact - tell her to stop being such a bitch and failing that, hire a bloody babysitter.
Having DS every weekend. Conversation. No, that does NOT work for our family. 50/50 care is better for all concerned. Involve lawyer and courts, if necessary.
Not being able to go overseas and Ex doing that exact thing. Conversation on 5th of January, EVERY DAMN year. Agree contact dates, approach to special occasions, holiday dates, approach to holidays, approach to emergencies. Put it in writing. Again, involve lawyer if required.
The DH taking fuck all responsibility is the problem here. Demonising the SM is a putting a bandaid on a heart attack.
Most posters just fancy sticking the boot in.
OP herself not helping herself by asserting herself and NOT advocating for both children by telling her husband to sort it out or fuck off.
What is it with MN these days, that rational and obvious, well thought out, polite posts are just ignored??? Not enough drama, or OP can't be bothered to read the responses on their own threads.
Probably too busy thinking about what to type next.