hiquestion in regards ***** ***** shares in a family

hi question in regards ***** ***** shares in a family owned/run business/co If the managers of co (mu father and brother in law) knew of an outstanding business loan was soon going to be paid off (that would significantly increase the value of my common shares, and did not tell me, but instead told me that my business shares were worthless and I should sell them while I could, (which I did, and subsequently found out a year later that the shares had been sold to them, from me, for about 1/5 of their value ... is this considered insider trading. the brother in law thus acquired controlling amt of shares in co for bargain basement prices. if this occurred 9 to 10 years ago, is there any legal action I can still take?

ps my father also had something to gain financially, as by saving $450,000.  (the amount he saved the co from giving the increased value on my shares had I waited and been paid the full amount meant the co then had enough money so that he could be repaid his money that he had loaned the co as it was getting started,...by placing the bro in law as manager my father guaranteed this person - bro in law - who had "pitched the deal" to me would also officially make sure the loan was all repaid back to my father many years earlier than it otherwise would have taken place

the only reason that I found out about the difference in share prices (before and after the loan was repaid) is because a sister died within a year and a few months after I sold my shares, and another sister  took care of the deceaseds estate, and sold her shares on behalf of the remaining son..the sister who handles the estate informed me of the new price on shares; and I stopped all communication with the bro in law and father.

final ps!

a couple of years after the share sale I went on disability for prev undiagnosed ptsd, depression, and mental disorder. I do not have much $ and am considering investigating either pro bono or legal aid or just walking away from the whole dysfunctional mess;  but thought I would start with you!