Seeing crying in dream is considered good as per those who believe in dream interpretation. In Hindu religion there is an ancient scripture known as Swapna Shastra which gives interpretation and meaning of various dreams.
The main belief is that those who see people, friends or relatives crying in dreams will soon see happiness. The meaning is that grief is over and there is scope for hope.
Please note that one should not give too much importance to such things.
Majority of the dreams have no meaning as they are just extension of important events that took place on a day. People see mainly dreams related to matters that touched them during the course of a day.