I learned harmony from listening to my grandparents sing together, and it also didn’t hurt that my Dad had many Everly Brothers 45RPM singles.
If you look at two-part harmony singing, you will notice that the vast majority of the notes are a third apart. In the case of the Everly Brothers, Don sang the melody, and Phil sang notes in harmony, mostly a third above. I often use the song “All I Have to Do Is Dream” to introduce this type of harmony to my students…
In one of my classes, we’ve made a project of taking music for different types of ensembles and transcribing them for ukulele. We’ve used music for recorder (Thanks Mom), brass and choir.
Here are the soprano and alto parts to a public domain choir arrangement of “Away in a Manger” played as a ukulele duet…