I thought it was just a phase when they stared bickering as they always got on so well when they were younger. The past year it’s getting worse and worse. There’s rare moments when they play nicely but most of the time they are purposefully trying to get each other’s backs up. They scream and shout at each other at least 3 times a day. I don’t know what to do, I’ve tried giving them their own space and talking to them about how they are treating each other but it makes no difference. Is this normal? Is there anything I can do? Will they grow out of it? It’s all so sad.