Let's be honest here, a mother in law will visit, and her daughter will be for it. In as much as you are the man and probably owner of the home, the alpha, and every other title you deserve, you only have to make sure you remember that every thing with women is a shit test. Wacha akuje, but make it clear to your wife about the maximum number of days she may stay. You will have won the battle with your wife, about being ready to 'accept' her family (women keep score) and at the same time taken away any potential stones that your inlaw may have been planning to use to stone your marriage. kusema wewe ni mtu roho mbaya hukaribishi watu kwako etc. Your mother in law will disguise her visit as having came for treatment, to see grandchildren blah blah blah, but being a woman and jealous as any other woman, she is really there to see how her daughter is handling the planteshen so she can either advise her accordingly or wrongly, based on where she stands on the morality scale. that car thing is because she wants to be given same treatment as her daughter. Even old women still want to believe they 'got it'.