Why do Brides Wear White Dresses ?

A son asked his mother the following question: 
'Mom, 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 Mom 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.'

The husband is still in intensive care and the prognosis is not good!!!