How to describe the sentence that grandchildren and grandfathers don't kiss grandfathers?

Grandpa Sun doesn't kiss Grandpa, which can be described as "Grandpa Sun United against Grandpa". According to relevant public information, grandson and grandfather are relatives of the same family, while grandfather comes from the external social field. Grandson and grandpa get along closely and understand each other better than grandpa, so they will have the same idea, and grandpa's idea is often unacceptable to both of them, so they will be dissatisfied.