Crying is one thing (tough to hear/endure, but generally not otherwise disruptive or dangerous.)  But refusing to sit buckled in is entirely different.  I have no issue sharing public space with a crying child - children cry!  But this little girl was not just crying from what I read.  One report said she ducked underneath the seat and would not come out and the parents still asked for more time.  

After a 15 minute delay already, I'm not sure the airline had a choice.  I mean they could not take off with the child not buckled in.  Forcing all the other paying customers to wait that first fifteen minutes and then however long it might have taken to calm her and get her seated seems unfair.

I've flown with any combination of crying children ages 2 months to 7 years.  But they are always safely installed in their seats!  If one of mine had done that, I probably would have voluntarily left the flight - just a very big version of leaving the grocery store/Target due to an over-the-top tantrum.

Jah puzzled over parents unpreparedness.  When the RastaYids flew with small children, we always carried a small bottle of ether and a rag in our carryon.  If our child scream and fall on floor and not get back in seat for 15+ minutes, we just apply ether to rag and rag to child's nose.  Works every time.  

Jah

Jah,

Seriously, Captain Benedryl is our co-pilot for every plane ride we have taken.  Works like a charm.

Sue me. :)