In 2011, Lillian Pearce hired a hit man to murder her mother-in-law, Sandile, as she was 'sowing divisions' between her son and Lillian.
You may be Lillian or Sandile and this is what I learnt from my ex mother-in-law, aptly named Mona.
Don't marry her son. She told you so.
Or, if you decide to go ahead anyway, announce your engagement, marriage plans and pregnancies with caution and consult her beforehand.
Reassure her constantly that she will always be No 1 in her son's life.
Accept that you will never be as beautiful, talented or intelligent as his ex.
Always give her a gift which you want, as it may be returned to you on your birthday/Christmas Day with a: "Someone gave me this ghastly thing, but I know you will love it."
If she constantly gossips about others, she is obviously doing the same about you.
The cookery, gardening, interior decorating or child-care course you passed with distinction was a waste of time and money as you should have asked her for advice.
She will fall ill if you do not visit her for every Sunday lunch, so you may receive instructions on how to cook, landscape your garden, decorate your home and care for her grandchildren.
If you prepare financially for loss of income while on maternity leave, she may ask your husband for a 'loan', while you are in labour.
Naturally, she gave natural birth to her son after forty eight hours of excruciating labour.
Should your children succeed, it is her and her son's positive guidance. If they fail, you are a bad mother.
If you and her son decide to divorce, she will no longer suffer from hypochondria, but have a new lease on life.
I have two amazing son-in-laws. Should they and my daughters have a disagreement, they don't need my meddling, as this is none of my business.
And, I will always be grateful to Mona for showing me how it should be done.