Can a lawyer who wrote my father's will may appear as my wife's council in a divorce case where the petition was filed by me. especially when this will is now not effective and subsequent will written by different lawyer is in force and my parents are no more
No he cannot if you can show that you participated in the discussion or was involved in the will process in some way and discussed issues with him which u would otherwise not discuss with another person. In short, u need to show that he was privy to certain information directly from you which could be material to your divorce case. In particular, if ur wife responds in any form referencing the Will, its a slam-dunk case of conflict of interest to disqualify him.
As the will written by the mentioned lawher not in existence and even there is no relevance of said will of your deceased father in the ongoing matrimonial dispute between you and your wife, there is no law of land which may create any legal hindrence for the mentioned lawyer to become lawyer of either of you litigating parties.