I looked & reread after your post but I didn’t see the hospitalization referenced. I’m not sure traveling is an added danger. If the baby was hospitalized and was discharged the discharge instructions would have covered any necessary precautions.
It’s a very sad event in any case although suing seems counterintuitive. Cherish the life that was lived, mourn the death. They are probably abreacting because of shock and the time of stress due to medical needs since birth.
Common sense says they shouldn't have traveled away from home.
The death is sad...the life was sad, too.
We know little about the parents.