Messenger Kids, Facebook's chat app for pre-teens, no longer requires parents to be on speaking terms before their offspring can start a conversation.
Children can only use Messenger Kids to chat with a list of contacts approved by their parents. Before now, if two kids want to message one another, their parents could only grant permission if they were friends themselves on Facebook.
It was a handy way to make sure your little ones only spoke to people you knew and trusted, but also meant their social circles were limited unless you befriended half the people you saw at the school gate. You might be nodding acquaintances, but do you really want to hear their political views and be inundated with their Farmville invitations?
Both parents still need Facebook accounts (Zuckerberg and company won't let you get away that easily), but you can now make and authorize requests without being forced to expand your own social circle. Just search for the other parent's name to send an invitation and wait for them to respond.