the kids meal is (in my experience) always mash, chicken nuggets, peas, fruit shoot, bag of M&Ms, yoghurt.

She will get the adult meal as the default unless you order a special meal such as a children's meal.

The only difference between flying to and from London is that the adult option can be pre-ordered ex-LHR but not ex-YVR. ex-YVR you will get a menu card with a choice but it will be subject to availability.

The adult main course option for the first meal will be from the Club World menu (but economy drinks and not quite as nicely served as in Business class). The children's special meal will not be. The second meal will be the same as in economy (and is generally small and nothing special). The breakfast before landing in LHR is especially disappointing.