White wedding dress

A son asked his mother the following question: 'Mum, why are wedding dresses white?'

The mother looks at her son and replies, 'Son, this shows your friends and relatives that your bride is pure.'

The son thanks his Mum and goes off to double-check this with his father.

'Dad, why are wedding dresses white?'

The father looks at his son in surprise and says, 'Son, all household appliances come in white.'