Can I still fight this in court even through it has been almost 7 years?

[funnylady1]

I am going to try and make a very long story short. In 2006 I got court papers that said my ex's sister and husband went to court and got custody of your son. In those court papers there was no mention of me, his mother. I went to legal aid to find out what I could do but I would of had to go back to the state which it was out of (New Jersey) and I live in Florida. Back when I got the court papers my ex and me were still together and he told me to go to the courts and tell them he took him from me. It's not that I want him to come and live here. I just really want to know what I can do. He is now 17 years old and I doubt he even knows who I am. I can't call there, since I have no phone number. He doesn't have any social pages, like Facebook and so on. I miss him very much. Can anyone please help.