Proud father

When his wife gave birth to a healthy baby, a proud father went in to work and told everybody that he has a 10Kg healthy son. After hearing what was going on, the wife tells the father to quit telling everybody that the baby is 10Kg because he's only 4 Kg. Next day at work, the father comes in and tells everyone that the baby is only 4 Kg. "What do you mean, he was 10 yesterday?" "Umm, well that was before he got circumcised".