You might want to start out with information on postnatal (postpartum) depression in general, talk about some of the symptoms, and mention that it's not only for women. Men often struggle with that kind of depression, but it's not something that's talked about very much - the focus is almost always on the mother. You could talk not only about the symptoms, but what fathers should do if they find themselves in that situation and how (and where) they can get help. More research is needed on the subject, along with more awareness that it even exists at all.