My longest plane trip was about 26 hours, from Perth, Australia to Ottawa, Canada, with stops in Singapore, Seoul and Vancouver. We did this many times when we lived in Australia, but the longest flight in mommy hours was the first time I travelled it alone with my two DDs (at the time one was 2.5 years old, the other 6 months). It was a VERY long flight, but the girls were amazing. Thankfully we were on Cathay Pacific, so I had lots of help from the flight attendants.
We regularly travel now from Chile to Canada...in fact, the girls (now 9 and 11) and I are travelling to Vancouver next month...10.5 hours to Toronto, followed by 4.5 hours to Vancouver, with a two hour stopover in the middle. It is SO much easier travelling now that they're older!
Foodwise...I used to travel with snacks for my girls when they were really little since they were picky eaters (peanut butter and crackers, animal cookies, fruit leather, dry cereal). We rarely ate any of it, though, so I don't bother anymore. Between all the snacks and meals on international flights (combined with inactivity), we never seemed to get very hungry.
As for the PP poster who mentioned about time behaving strangely when your travelling...yep, I agree with you. After about 5 hours, I think you just sort of sink into a kind of stupor (oxygen deprivation?!) and time seems to disappear. Either that, or we kind of blot it out of our memories like childbirth

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