We (my wife and I) have a long trip ahead of us and we have a 20 month old infant. I know that infants have no seat but it is very hard to hold a 20 month baby boy during a long flight.
So I am wondering if it is possible to by him a child ticket so he could have his own seat?
Do airliners care if I reserve a child ticket for an infants?
Yes, you can most definitely purchase a "Child" ticket for your sub-2 year old infant in order to secure them a seat. As you're obviously aware there's generally no need to purchase them a seat if they are under 2 years old (although you may still need to buy them a ticket that lists them as a lap-child), however if you do this then you will potentially have to hold them the entire flight.
Depending on the airline you may find that there is no such thing as a Child ticket (or if there is, that it is the same price as an Adult). Even if there is a discounted child ticket it's worth checking to be sure if there are any other differences between that and a normal adult ticket - sometimes the difference in price is minimal (eg, a 10-20% saving) but the child may have a lower baggage allowance and it may actually work out cheaper to purchase them a full ticket and use their allowance if you have additional checked bags.
