Not sure how Ryanair works in Europe, but the cheap airlines in latam had to give you join seats with arw travelling with minors, but to only one of the adults, so usually a parent travels with the kids and the other on a random seat.

In my last fly I offered to change seats with the other parent and they were like omg thank you, but internally I was thinking on myself because I didn’t want to travel side to a random kid.