Originally Posted by stupidhead

Sure, as long as the family on a BE ticket doesn't get to displace a single passenger on a regular economy ticket who paid extra for the ability to pick their seat, or worse, picked a preferred seat at a premium.

When you book a Basic ticket, UA.com makes you confirm no less than a dozen times that 1) you do not get to pick your seat(s), 2) the computer will assign you one at check-in and you will like it, 3) there is NO guarantee that you will get to sit together, and 4) the above are acceptable to you. If sitting next to your child is important to you and you bought a Basic ticket, that's your fault. Personally I make it a rule never to book basic economy or equivalent fares under any circumstances for myself and anyone I book travel for.

DoT threw a hissy fit over a non-existent issue when a remedy clearly exists - pay up for a regular Economy ticket or pay up for seat selection if on a BE ticket like everyone else.