I believe that every measure will be taken during the trip to ensure that the baby is well taken care of to the highest of standards, I think that as long as the parents wish for their child to come with them on the trip then there is no problem with it.
I don't think there's a problem with an eight-month-old baby taking a long haul flight. If it wasn't okay for Prince George to travel to New Zealand and Australia, they wouldn't have taken him. There are guidelines and advice on taking children even younger on planes, so long as they have their bottles at take off and landing to protect their ears, there isn't a problem.
I think the media should leave the Royals on their own. It is totally up to them whether they take their 8 month old baby with them or not. It is not like the baby would be doing all the official work. Its absolutely fine for an eight month old baby to travel to N.Z. and Australia with his parents.
This really outrages me: how is it possible that a certain someone can even consider on putting a tiny eight months baby through such a large and uncomfortable trip? Is common sense totally lost from the map of our human values? This is a really bad syntom of society's degradation.