GEN1551 If one has a child, close friend or relative in another city and wishes to keep abreast of his affairs out of genuine love and concern for his well-being, then it is permitted to inquire of acquaintances living in that city, as long as it is made clear that one’s motives are positive.   Zera Chaim 4:11 In such a case, the person being questioned is allowed to answer truthfully, as long as his motives are beneficial as well. This also applies to a teacher who maintains a close connection with former students and wishes to keep informed of their progress, especially if he can help them in any way to develop in a positive direction or prevent them from straying. One of the sterling qualities of a righteous person is “to carry a burden with one’s friend.” A righteous person is genuinely happy in others’ rejoicing, and sad with their pitfalls and misfortunes. When such people hear negative news about another person they will not think less of them, but will be saddened by their pitfalls. Unfortunately, our hearts are not pure, and hearing about someone’s negative traits inadvertently involves some maligning of the person’s character and therefore is lashon hara. Nevertheless, some relationships can come very close to the ideal. The Torah describes Yaakov’s inner connection with his son Binyamin: His soul is attached to his soul [this verse]. Similarly (I Shmuel 18:1), The soul of Yonasan was bound with the soul of David, for he loved him as himself.  In such cases the source of questioning about the welfare of that close person is purely to “rejoice in his well-being and to be saddened by his pitfall or misfortune,” with no trace of maligning character. A conversation in this spirit is not lashon hara. EHRMAN  207-8