Im sorry but we can not tell you what is going on with this 20 year old son in law of yours.

(since you are new please seeing disclaimer at the bottom of the page )

you call this 20 yr old your son in law... a son in law is a guy who is married to a persons own daughter or son. what does your daughter or son that is married to this 20 year old in question... you see what ever happens with the son in law is now between the daughter/son that is married to this man and this man their selves. it is them that needs to work out what to do about this situation.....

that said some questions for you...

you have actually witnessed your ......son in law and his mother........ in bed together? your son in law climbing onto his mothers lap, nuzzling her neck, talking like a baby?

or are you getting this information second hand?

this makes a big difference on whether a person is witnessing something their self and whether they are getting the story from other people and what the context of the conversation is when getting a he said she said story about someone.

my opinion is that if ............I......... witnessed this behavior I would question why I was in someone elses bedroom watching my daughter / sons husband climb all over the husbands mother.

I wouldnt normally be in someone elses bedroom watching this kind of thing but if it happened that for some odd reason I was, I would call the police.

you see if this 20 yr old son in law is mentally or physically challenged and this mother was allowing an incestuous relationship behaviors thats a crime.........here where I am..........

incestuous relationships are when family members act, behave in sexual ways with each other... mother child (no matter the age of the child), father child (no matter the age of the child) , sibling and sibling (ages dont matter),

here in the USA it is illegal for people to have incestuous relationships. that is why if I witnessed such behavior I would make a report and let the police do their investigation, if there are special circumstances the police would be the ones who know what is best for this family.

If I was getting this story of what happens from my daughter or son that is married to this 20 yr old. I would ask my daughter or son what they want to do about their husband acting like this. Then I would leave it in their hands (the married couple) to work out their marital problems. Im just not one to get into a he said she said battle with what my relatives husbands and wifes do. I leave it up to them to work their problems out.

for you, my suggestion is if this continues to bother you contact your police department who can investigate whether your daughters husband is mentally challenged and why his mother is allowing him to have an incestuous relationship with her. and contact a mental health treatment provider who can help you in working out how this is affecting you.