best option is to keep 24 hours helper for in laws 

2) in the alternative shift in laws to senior citizen home providing assited living 

3) in the laternative shift to flat near yoiur in laws 

4) not advisable to stay with in laws 

She can file complaint against the same with police but for only apprehension that she will file any malacious prosecution no remedy can’t be exercised in advance 

Dear Sir/Madam,

In Canada, your sister should treat every suicide threat as real: call 911 (or 988 for suicide crisis support) each time, and keep copies of all texts, calls and messages. (Canada)
A person merely naming them in a threat or note does not automatically make them legally liable; police action still requires evidence and reasonable grounds. (Department of Justice Canada)
If the threats or harassment continue, they can ask local police/court about a peace bond, which is a court order used where someone fears harm. 

If the mother-in-law (MIL) makes a threat, your sister needs a record of it to prove she and her husband are being harassed, not the other way around. She can record phone calls or in-person interactions where threats occur can be vital.

She can file a "Police Intimation" or a "Station Diary" entry at the local police station. This is not an FIR (criminal complaint) but a formal record stating: "We are being threatened with false implication and emotional blackmail; the individual has a history of mental health issues; we have moved out to maintain peace." This acts as a crucial "pre-emptive strike" if a case is filed later. In many jurisdictions, threatening to commit suicide to frame someone constitutes criminal intimidation or extortion. A lawyer can help determine if she should file a formal complaint regarding these threats.

Courts have repeatedly held that if a person is highly sensitive or mentally ill, and their family has simply distanced themselves for their own well-being, that distance does not constitute abetment. Your sister moving out to live her own life is a legal right, not a crime.

If possible, communication should happen through a third party or in writing only.

 If the MIL threatens suicide, instead of engaging, your sister or her husband should immediately call the emergency services or a suicide hotline to report it. This shifts the responsibility to professionals and creates an official record that the family tried to get her help.

Has she or her husband already made any formal reports to the police about these threats?

Dear client

Your sister is in a vulnerable state both legally and psychologically. Threats of suicide are being used as leverage against her, which makes it necessary for her to take preventive action and establish a legal record.

1. Document everything, including WhatsApp chats, phone calls (if applicable), and messages that contain threats (for example, “I will blame you”). All this documentation will serve as critical evidence in denying the act of abetment of suicide under Section 108 BNS.

2. Immediately after collecting your documentation, you should send a written complaint to both the local police department and to the SP via email. In the complaint, include:
A) Information about your mother-in-law’s mental state and that she is currently in a mental health program;
B) A history of suicide in your mother-in-law’s family persists;
C) Any ongoing threats of false implications.

By filing with both law enforcement entities, you will have created a record that will protect you in the future if/when she decides to falsely accuse you of something.

3. You should file either a NC (non-cognizable) or diary entry for harassment and intimidation. Regardless of whether an FIR is issued, this type of filing will documented the aggressors actions.

4. You could file a preventive writ under Article 226 in the High Court for protection against false implication and police harassment.

5. You should maintain physical distance from her so that you avoid being in proximity or experiencing a confrontation.

6. If the threats continue to escalate, you should have law enforcement conduct a well check on your mother-in-law.

Do NOT ignore threats. In these situations, documenting the events and filing your initial complaints will provide the greatest protection possible against future false accusations by the aggressor.

At the outset, it is important to clarify that mere threats of suicide by the mother-in-law, even if accompanied by statements naming your sister and her husband, do not automatically create criminal liability against them. For any offence such as abetment of suicide to be made out, there must be clear evidence of instigation, intentional aid, or active involvement. Emotional pressure or strained family relations, by themselves, are not sufficient in law.
However, such threats are often used as a tool of coercion and can later be misused to create legal complications. Therefore, your sister should take preventive legal steps to safeguard herself.
The first and most important step is to create a documented record. Your sister and her husband should communicate in writing (preferably through messages, emails, or even a formal letter) clearly stating that they are not responsible for any such act, that they are concerned about her well-being, and that she should seek proper medical treatment. This helps establish their bona fide conduct.
Secondly, if the threats are frequent or serious, a preventive complaint/NC may be lodged with the local police station stating that the mother-in-law is issuing suicidal threats and falsely implicating them. This acts as a protective record in case of any future incident.
Thirdly, given that there is a known history of mental health issues and medication, it is advisable to preserve any available medical records or proof of treatment, as this becomes relevant evidence to rebut any false allegations later.
If the situation escalates, your sister may also consider sending a legal notice distancing herself from any such threats and placing responsibility on the concerned individuals, which further strengthens her defence.
It is also important to maintain physical and residential separation if relations are strained, as continued proximity often complicates such situations.
The advice given to “simply reconcile” is not a legal solution where there is manipulation or threat. The law does not blindly favour parents in such circumstances; rather, it examines evidence and conduct.
In conclusion, your sister should focus on documenting everything, creating prior police record, maintaining distance, and avoiding any confrontation, so that in the unfortunate event of any incident, she is legally protected and can demonstrate absence of any wrongdoing.
Please feel free to reach out if you require assistance in drafting a preventive complaint or legal notice.

Sir/Madam,

In the present circumstances, your sister may take help of NGOs/Nari Niketans who are helping women in distress and they will provide an instant support by revealing the stress and difficulites faced by your sister. At the same time, your sister and her husband can install secret CCTV cameras to record the things happening there and this will be  a direct proof for their save guard in case of false and bald allegations against them. 

Your sister has clear legal recourse. The mother-in-law's suicidal threats constitute "criminal intimidation" under Section 351 of the Bhartiya Nyaya Sanhita (BNS), 2023, punishable with up to seven years of imprisonment if the threat involves death or grievous hurt. Additionally, this behavior qualifies as "emotional cruelty" under the Protection of Women from Domestic Violence Act, 2005, which recognizes threats of self-harm as a form of verbal and emotional abuse. She should immediately file a police complaint to document these threats and can also approach a Protection Officer or Magistrate under the DV Act for protection orders restraining her in-laws from contacting or threatening her. Contrary to the local lawyer's advice, the law does not favor perpetrators of threats; proactive legal action is essential for her safety.