we cannot tell you why your previous petitions to modify child support were denied. they were. that is unfortunately the end of it.
if she is now 18 and out of high school, you are not entitled to any more support. but, if you have a petition pending, the court could go back to modify the support from the date of notice of that petition until the attaining of age 18 and high school graduation.
if he is $4000 behind, he owes you that plus interest on the back support at 9% from the end of the month each payment was due until paid in full. i suggest you hire a lawyer on a contingent fee basis to collect the arrearage and the interest. he could also be held in contempt even tho you daughter is now 18. the statute says so.
You mentioned "they" several times but we do not know who "they" is. If you daughter has attained the age of majority, there is little you can do. You should have hired a good lawyer as much as 15 years ago. You can hire one now to go after back child support plus interest. If your daughter is going to college, you are entitled to ask for contribution to child support too. It is very unfortunate that you relied on someone who did little for you but part of that is your fault for not being a little more aggressive over the years.
I agree withe previous answers. You cannot go back now to request modifications since your daughter is emanicpated (unless she still has a senior year of high school), then you may be able to request an increase, but depending on the length of time the increase would be and his earnings, it may not make economic sense. As suggested before, you should get an aggressive attorney to go after his arrearages and the interest you are owed. Best of luck.
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