One approach I employed may help readers keep track of the spreading number of family members.
In drafting my novel What’s Left, I envisioned each chapter as a module that could stand alone from the rest of the book. Think of it as a short story. That way, the number of characters in each chapter is more focused.
And while first names are usually repeated frequently in a Greek-American family, I limited this to just one great-grandmother and one descendant, and used a nickname for the elder one. Neat, eh?
Yes, the family members do show up in other modules and there is continuity over the whole, but at least you don’t have everyone in your face at once.
When you go to a social event and are introduced to many new people, are you able to remember their names and faces? Or do you go into a blur? How do you cope with this challenge?
Jnana's Red Barn 