Your house?

You can make complaint against them under section 504 of IPC

Section 504 IPC as defined in the code provides punishment to, “whoever intentionally insults, and thereby gives provocation to any person, intending or knowing it to be likely that such provocation will cause him to break the public peace, or to commit any other offence, shall be punished with imprisonment of either description for a term which may extend to two years, or with fine, or with both”.

Plus you can make complaint against them under DV act.

there are some MIL who don't want to see the happy life of their children you said she is mentally ill so  ignore her comments. However, I will not suggest any legal action against your mother in law. It is better for both of you spouse. 

If you prevent them they will directly accuse you of cruelty as stated by court, instead file domestic violence upon them, detailed discussion is necessary to make you understand pros and cons

See you can file a complaint of domestic violence and mental cruelty agaisnt In-laws in the police station and a FIR can be registered but you should take not of the fact that this can increase difference between you and your husband.

No you cannot. If you do, then it becomes a ground for your husband to file a divorce.

You have 3 options

Ignore them

Accept them

Retaliate

Since you are pregnant, I would suggest to ignore them for the time being. Later when you're back to normal you can think as to what you want to do. Even if law exists, I would recommend to stay put, coz as of now you are not in a situation to fight.

And understand that you are better off ignoring. The more you hate them you are giving more chances for them to affect your peace of mind.

Google for law of attraction and watch those videos.

You can file DV case against your mother in law and husband seek protection order , right to stay in matrimonial home abd maintenance from husband for yourself and kids 

Real harassment means, you can file the complaint in police station and get them warned if required.

Collect evidences of mental health issue if ur MIL and you can claim in that regard.

Handle causally and go smoothly as they are patients. 

1. As per the information mentioned in the present query, make sit clear that you have been harassed and tortured for no fault at your end.
2. The behavior which they have been showing, is simply not acceptable at all.
3. There is no such law which can say that you can stop their entry in the house.
4. But, if you happen to file a police complain against them for torturing you after coming to your house then here are chances where they may be stopped by police.
5. This step may create more problem in your married life.
6. You should also try to talk to your husband about this to not to create any more nuisance for you and your child.

This is a very common emotional behaviour in case you are pregnant then you are worried about your child at the same time your in laws are worried for the child as well I think you should take things easily your very possessive about you well being and hopefully not taking your in laws as a family anybody can go to the hospital if he is sick and take the medication until he or she is ok your husband was an on this is not a disadvantage I disqualification and it is your responsibility to check bill before you get marry that whom you are going to marry as you say that your husband is behaving nicely and it is for a few days business when you are in love come to your place and this is your responsibility as well to keep them happy so that you can be happy that should be some tolerance level in a state of involving in big fights which is giving you the impression that you are being harassed and at the same time giving the impression to your in laws that you are not a good daughter in law both of you you should understand your position this is not going to continue for long as your family is growing and at the same time you have all the responsibilities to maintain your family together your in laws.

1. Whose house is it?

2. You can file a DV case under Section 12 of DV Act to seek a protection order against your in-laws and also injunction to restrain them from coming to the shared household in which you reside with your husband. This is the maximum you may do to restrain them from coming to the house.

3. A criminal complaint for harassment can also be filed under Section 498A,

1. The acts of your in laws is certainly not normal and smacks of crime as well for which you can explore legal options as well.

2. However taking recourse to law may jepoardise your marriage. hence try to resolve the dispute amicably by sitting with respective family elders.\

3. If all talks of compromise fails then you can lodge complaint u/s 498A IPC along with case under PWDV Act.

You cannot prevent them from visiting their son's house.

You can tell them strictly to not to behave in this manner which hurts you, if they dont listen then you may file a DV case against them seeking protection and other reliefs. 

But be prepared to face their more atrocities if you would opt to approach legal forum for solving this trivial issue.

Even your husband may not support you after that.\

Alternately you may prefer to rope in elders from your side to intervene and advise them and also warn them strictly about this or else to face the issues legally.

Any legal action may hamper your peaceful marital life, hence you may have to exercise abundant caution while handling this sensitive issue.

Dear Madam,

Most of the women in the country are unaware of these circumstances which would amount to cruelty and gives them a right to use a legal weapon against her in-laws. The provisions of law dealing with the harassment of a woman by her in-laws are Sections 498- A, 509, 304-B, 306, of the Indian Penal(IPC), the Domestic Violence Act, 2005 and Dowry Prohibition Act, 1961. It is better to file dowry harresment case against your husband and in-laws in Police Station. or file a Domestic Violence case in Family Court.

Section 498-A, Indian Penal Code

This section covers the cruelty committed either by the husband or by any relative of the husband against a woman

Section 509, Indian Penal Code

If any persons intend to insult the modesty of a woman through any phrases, words, act, or gesture shall be punished under this section

●     Section 17, Domestic Violence Act, 2005

If a woman is being subjected to domestic violence and she has filed a case against her in-laws regarding this, and for this very reason they are not willing to her with them in their house then she can an application under this section and after examining the application the court may give directions to her in-laws that she shall not be excluded from her matrimonial house.

You can take a restraining order from court if the said house belongs to you. You can also file Complaint of domestic voilence against them