We flew coach on United, and we did spring for the third seat for our daughter. We did not take a car seat. We held her in our laps some of the time, but she was also able to nap in her seat, and even sat there and played some. (I have to admit that we also used it for a couple of diaper changes, as the changing tables in airplane restrooms are not easy with a very wiggly baby, and there is no way for 2 adults to get in there to change a diaper. They have no safety straps on those changing tables.--Please excuse the tangent.) Anyway, even when Mary Joyce was in one of our laps, the extra seat provided a good place for stuff and gave us the space that we needed for making bottles and everything else that we needed to do. It was definitely worth the money. (By the way, it also gave us access to an aisle seat, which we did not have on the flight over. We flew Chicago to Beijing on the last row of the plane in the middle 2 seats. Talk about miserable. The flight home was much better, even with a 9 month old.
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