Chofetz Chaim Daily 8 Av 8:10 Asur to say LH to anyone; men, women & children. Telling your spouse every time someone wrongs or insults you will involve them in fight. Eventually s/he will lose respect for you when s/he sees you’re always being teased. 8:11 Asur to say LH to relatives, siblings & parents.
Chofetz Chaim Daily 9 Av 8:12 Asur to speak LH to a Jew. To a non-Jew is much worse because it causes a chilul Hashem. As well, the non-Jew will definitely believe it and cause the Jew great damage. Even more terrible is informing on a Jew to authorities. This is equal to apikorsus and great punishment awaits.
Very inspiring video about Lashon Hara https://www.youtube.com/watch?v=tnxvYCYaK_k
by R’ Ephraim Wachsman