You may be right Prof Davey, I was just hypothesising. No, I do not think it is right for people to have their flights changed at short notice. I'm surprised anyone had to wait two days for another flight though.
Well I guess it depends on the booking arrangement - some tickets allow transfer to other airlines (and are usually the more expensive tickets). If you pay bottom dollar you may need to wait until there is space on a flight from the same airline, and that could easily be a couple of days.
I guess as he had been disembarked because of ill health the airline would need to be confident that the child was fit to travel.
Going back to my story about the woman being chucked off the plane because she was claiming she was ill and needed to be upgraded. This was 9 hour-ish flight from the Caribbean with the family. Everyone was fine when we boarded, but by the time we got off the plane our daughter had broken out in chicken pox. There was no sign of this as we boarded although in hindsight she had been a touch under the weather for a few days before hand. Had those chicken pox appeared just a few hours earlier we wouldn't have been allowed to fly and we probably wouldn't have been allowed to fly for days as she would have been infectious.