A worried Mom, my 4 year old suddenly started stuttering after my wife had a party that petrified him bc of strangers and noise. Wonering about trauma and stuttering...

A worried Mom, my 4 year old suddenly started stuttering after my wife had a party that petrified him bc of strangers and noise. Wonering about trauma and stuttering... My 4 year old child started suddenly stuttering. Im a psychology major and work with developmentally disabled adults. My wife decided to throw a party amd my son with stage 2 kidney failure and other physical issues hasent been around alot of people and now with covid barely any social events. The people at my house were strangers to him and im divorcing her and in my own room. He kept running yo me and saying he wad afraid someone was going to take him. He was screaming " get out of my house" and throwing stuff. The next day he started the stuttering and id afraid and thinks that people are coming over again, any noise he yells what is that! And says he doesn't want to be near another party. He wasn't told there will be people here you dobt know or introduced. My wife thinks its not related, hes doing it on purpose , and is "crazy" for his behavior. Im disgusted with her and im the biological mom tsking care of his every need and she does NOTHING anymore besides party work and sleep. I know he's traumstized and in taking loving his mom making us do family time anything for comfort. I know im starting speech ther2apy up asap as he used to make becsuse he spoke later than other with trouble but I need to know more about child psychology as I was told it can sometimes make things worse att certain ages.hes very different with how he is with my as he knows my devoted love and spend 24/7 with him taking care ofnhm and she screams and is absent alot which is much better. When doing fake lovey stuff I went to hold her hand and he flipped out screaming for her to get off of me, probably thinking hell less from me. Does anyone know about traumatizing kids and suffering or what to do. Sometimes its not there in sentence and sometimes he can't get a word out. Interestingly when put in the phone with him Gammy, his workd, he diddnt stutter once! The second time he was but all not focusing and all over the place. Thabks so much jm talking to his drs and old therapists tomorrow but aby ideas advice and info is so appreciated!