Usually my 15yr old ds and 13yr old dd ignore each other (on a good day) but every now and then ds will be in one of his contradictory moods and has to comment on every single thing dd says. She then explodes and shouts/yells/screams at him - going from quiet 13 year old to screaming banshee.
If dd is telling me something, all ds has to say is oh yeah, I bet it wasn't like that, or I bet you just imagined it and she blows up and storms off to her room for the rest of the day.
If I tell one of them off I'm taking sides and am told I should tell the other one to stop. So, should ds just shut up and never comment on anything dd says or should dd try to control her anger explosions and learn to just ignore ds?