How Do I Make This Slightly Sweet, Southern-Style Tunafish Salad?

(Image credit: Apartment Therapy)

I do have a nice recipe for a tuna salad with black olives and apples, which is great, but I have been unable to achieve that sweetness no matter how I try. And I am no rookie in the kitchen! Help? Advice? Thoughts? Thank you.

Sent by Lorraine

Editor: Readers, are any of you familiar with this kind of tunafish salad? Any ideas for recreating this recipe?