Was on a trip to Panama and had to fly via Spain with 2 small kids (that flight was later shown in a TV doc about scary flights). Had to overnight it Spain and on check in discovered that the UK check in had not assigned us seats. Each of us in a middle seat different rows, different parts of the plane. No one would switch. I almost got to the point of saying fine - good luck looking after my 4&6 year old for the next 12 hours before someone on the other side of the plane switched.