Why my baby was affected by g6pd but us the parents ddnt see any deficient on this?

X linked recessive: G6pd deficiency is an x-linked recessive hereditary disease. In males ( who only have one x chromosome)-1 altered copy of gene in each cell is sufficient to cause this condition. While in female -needs both copies of genes altered. Thus it's more common in male.It is possible that a mother is a carrier ( only one x chromosome is affected) and her baby boy has this condition.

Based on your info: I assume that you had a baby boy...Congratulations.! also, because g6pd is an x-linked disorder, i conclude that your wife is an a symptomatic carrier and you have a normal g6pd gene. Your son got his y chromosome from you and his x chromosome from your wife. Your wife is asymptomatic because she has one normal copy as well, and because of random x inactivation she has adequate g6pd expression.