What do you do when your dad gets a girl pregnant while he is still married to your mom?

honestly there is really nothing you can do.. its up to your father and mother to figure out how this is going to be handled. as far as the slander goes all she is is a bitter mistress of a man who will not leave his wife for some unknown reason. and for all the people who believe it are no better then she is and shouldn't mean anything. in situations like this unfortunately there is always going to be rumors and resentment along with drama its inescapable you do not have to embrace this woman if you dont want to thats your choice and your choice alone. infact its your choice if you chose not to have a relationship with your new sibling. one of the problems that you face is there is only one side of the story being told at one time. which gives way for the gossip that takes place i would know because when me and my husband were going through our divorce he spoke about me to his friends and his new girlfriend and somehow i was the bad person out of the whole situation and everything was my fault but yet no one bothered to ask me why i wanted a divorce from him in the first place... regardless the best thing for you to do is to stand up for your morals and beliefs naturally in a non violent way... support your mother in her time of need and things will work themselves out at some point. i always say things happen for a reason even if you dont know what it is yet... and karma will come back and bit you... and it will hurt... good luck