I think the confusion (with the program, and possibly with some of us learners) is that in English "boys" can be used as "sons" and "girls" can be used as "daughters" in the right context. As in "I have to take my boys to hockey practice." Perhaps the program offered up "boys" as a translation of "Söhne" for that reason, but, from everything I've seen so far, in German Jungen and Söhne are not interchangeable.