Originally Posted by
rjque
I've flown hundreds of thousands of miles with my (now 9 year old) daughter, and this has been the rule on every airline we have flown for all that time.
In booking some flights in Europe this summer, I learned this rule doesn't apply everywhere. Ryanair had no concerns with me reserving seats for adults in the edit row with the kids seated one row behind, all on the same booking. So this may be a US rule/standard/norm.