It explicitly told you that you couldn't choose your seats, and you took that to mean everyone would still be seated together?

How often do you travel? Picking seats in E has been a feature for years and years.

I thought that on the United website you can pick your seats in Economy on domestic or International flights during booking. It's just the seats in Economy + that you can only choose if you have a certain status or pay additional money for them. But with Basic Economy, you cannot choose your seats (unless you pay additional money).

This thread has been very...enlightening. Whenever I've priced out options to fly somewhere with my wife and 6 year old, I've been under the assumption that if we want to sit together, I need to include the price to "upgrade" out of basic economy when comparison shopping. Now I'm beginning to see that paying that extra fare may not be necessary.

You made no prior mention of an infant.

Regardless, there should be no assumption that a family of four will be seated together if seats can't be chosen at the time of booking.

I think on some planes there are some rows that don't have enough of the oxygen masks in case of loss of pressure to cover a lap infant.

What airline are you flying?

That is only a portion of the solution -- many use Expedia /Orbitz/ .... their handling of this situation is less clear to the purchaser (and unknown if even what is presently available was in place when the SIL purchased). Until the OTAs provide appropriate notice, this problem will re-occur.

There is a big difference between "you can't choose your seats right now" and "you may not be able to sit together".

On Southwest, no one can select seats in advance, but the airline definitely makes sure that families sit together.

At movie theaters, stadiums and concert halls without assigned seating, you can't choose your seats in advance, but you can definitely sit with your family.

It's not unreasonable to assume that "no seat selection" means that you can't choose your specific seats, but you will still be able to sit with your kids.

No, there really isn't, particularly for people who fly more than once every few years.

"You can definitely sit with your family"? No. It's first come, first served, and the ushers don't move people to accommodate later-arriving families.

In other words, you will buy a product that is clearly totally unsuitable for your needs, then kick up a huge stink and force the airline to give you the features that you have refused to pay for.

This is why airlines need to stop giving in to blackmail from people who are determined to get something for nothing. The more people are allowed to get away with gaming the system, the more people will do it.

The only solution is just to stop groups which include minor children from buying Basic Economy. People clearly can't be trusted to act responsibly.

Should the limit be "minors"?

I remember flying (presumably WN, but I can't recall) with my parents and a friend when I was around 16. None of us sat together. Two of us were minors. There was no issue there. No one cared.

Obviously a 2 year old needs to sit with someone, but it's not clear whether a 16 year old, 12 year old, or 8 year old does.