To the beginner to blossom the joke about the bride vs. the maid:

To live together is evil. They all know. Everyone knows this before the wedding.
Secondly, it is unlikely that the son with his wicked wife was drawn suddenly and unexpectedly with suitcases in the middle of the parent’s single. This issue was discussed and a reasoned decision was made.
The success of this initiative depends on the iq of both sides. If you accept a new, strange person in the house, you will be prepared for inconvenience. If you come to live in someone else's house with a well-established household, do not lie down and respect other people's orders.
As soon as the struggle for power begins or attempts to put it in place - turn off the light, throw a grenade.