[lucb1e]

I figured as much. But my grandmother has no smartphone (nor have I), and nobody from the list of recommendations was directly connected to her. And there are people missing, even if the phone number matching was the only way. These two things are what I find weird.

[Xuzz]

But your two cousins, who may have smartphones, could both have your grandmother as a shared friend — and thus, since they were both connected to you and were connected to your grandmother, Facebook assumed you might know your grandmother?

[lucb1e]

Good idea, but I thought of that. They don't have my grandmother as shared friend (she's from the other "side" of the family as we call it, not sure if that's proper English).