How can I make my uncle and mother-in-law live in harmony?

My uncle and my mother-in-law are twice as many people. As for how to deal with trivial matters in life, this relationship is the same as my mother-in-law. In the eyes of her mother-in-law, my uncle will always be a person with a foreign surname, and my daughter is the bridge and link between you. It is understandable that there may be differences between the two generations. As long as it is not a matter of principle, it should obey the elderly. Another point is not to quarrel with your mother-in-law.