Most of them were brought on by stress, particularly That Time Of The Month. I well recall one that she had after accidentally hitting her head on the underside of the communal stairwell here in the block, which was completely out of the blue, but fortunately short.
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'