mother in need of help

i have been divorsed for 2 years now and we have 3 children, 22,19 and 12. my ex is a police officer that doesnt seem to be very truthful. he has recently turned out 19 year old against me which has been very hard. He is soon to remarry the women he has cheated on me with twice. he never told me about this i found out from and old freind. our 12 year old is very upset and doesnt want to be around her father when she is there. I have also found out that when we got divorsed he said he was making 36,000 and the truth is he make around 72,000 a year.
My question is doesnt he have to notify me of chnges that effect out 12 year old daughter?
does he not have to notify someone of the amount that he makes? he obvioulsy isnt paying the right amount of child support

[tbyte]

He is supposed to notify the Child Support Enforcement Agency. You should let them know, and ask for an adjustment based upon past income, retroactive to the year or your initial judgment.