Sunday afternoon, dad was sitting in his favourite spot high on the spire, and mum flew in, landing on the base of a pinnacle. She looked worried and very alert. She kept peeking around the pinnacle as though looking for something, or someone. None of the juveniles were in sight. Where were they? She squawked loudly at dad, and he obediently (though rather unproductively) moved and sat on the edge of the nest turret, looking in at the empty nest. Now she was happy that he was keeping a lookout for their youngsters, she was able to have a rest so went to sleep. He sat, wide awake, looking out for the kids to return. After about half an hour, he gave up and dropped to the narrow ledge below the balcony & turret, sheltering from the wind. Mum moved up to his favourite spot to take over lookout duty, and nothing had changed when I left. I heard later from a friend that the juveniles did all return safely, and somewhat noisily.