The Big Sissy

One summer evening during a violent thunderstorm a mother was tucking her son into bed. She was about to turn off the light when he asked with a tremor in his voice, 'Mummy, will you sleep with me tonight?'
The mother smiled and gave him a reassuring hug.
'I can't dear,' she said. 'I have to sleep in Daddy's room.'
A long silence was broken at last by his shaky little voice:
'The big sissy.'