Sick humour

Mother comes home from a business trip and asks her little son,. 'Well, Johnny, how did you get along with father while I was away?'
'Everything was fine, mum,' the little boy says. 'Daddy took me to the middle of the lake by boat every morning and I swam home alone.'
'Wasn't it too much for you to swim?'
'Oh, no, mum, the only problem was that I had to get out of the bag first.'