The tendency for a young family to live separately from their parents started forming centuries ago. In Oceania, some tribes had a tradition, which did not allow them to sit at one table, they were not supposed to talk in each other's presence. In Polynesia, young couples were not supposed to see their parents for two years. In several Kenyan tribes, it was a lifetime tradition. Australian natives were not supposed to pronounce a son-in-law's name ever.
On the other hand, in Zambia, a son-in-law did not have a right to sit down in his mother-in-law's presence. There were some laws, which did not allow a son-in-law to start eating before his bride's parents. There were a lot of other limitations like that, which created a lot of discomfort, because relatives had to look for someone else's help to talk to each other.
In the past, people had a lot of problems in communication between relatives. Some peoples did not allow a son-in-law and a mother-in-law to see each other; if a wife had a sister, a husband was not supposed to stay alone with her ever. The same rule worked for a wife, who was not supposed even to look at her husband's brother.
Some nations had special rules that were used in case of a casual encounter between relatives: to cover the head with a kerchief, to close eyes, to turn around and walk in the opposite direction, to lie down and wait for them to pass by and so on. It is worth mentioning here that all those traditions and customs were practiced by the nations geographically separated from each other. One shall assume, there were very important reasons for it.
A lot of nations have numerous legends about incest. They are all common for the horrible trouble that spirits and gods brought down on people for that sin. In certain tribes, husband's and wife's relatives had a right to render sexual services to young people on certain occasions. It was particularly practiced in Indian tribes. In North America, a mother-in-law had a right to become a sexual partner for her daughter's husband during the first days after his wife gave birth to a child. Nigerian warriors often competed with each other, and the winner was lucky to enjoy the prize - someone's wife.
All these things were happening many years ago. Nowadays, parents often make young families collapse. In Western countries, for example, a man has a right to regulate the frequency according to which his wife will meet her parents.
Near the United Nations Glass Palace in New York, there is a metallic sculpture entitled "Evil Defeated by Good", representing Saint George transfixing a dragon with his lance. It was donated by the USSR in 1990 to celebrate the INF Treaty concluded with the USA in 1987