I know The Rock is related to The Usos because they are his cousins, in other words they are his family members but Jimmy and Jey have never interacted with The Rock and The Rock has never interacted with Rikishi's sons, and I would love to see them interact with each other as well considering the familial ties
Rikishi is the Rock's cousin, so the Uso's are barely even related to the Rock. There's nothing really to gain from having them interact on TV to be honest but WWE may do it just for the sake of having a little moment that will be forgotten about the next week.
I read somewhere recently that rikishi and rock are not technically blood related, it was more to do with the closeness of samoan communities, rikishi is related to Haku and Tama who would refer to High cheif Peter Maivia as 'uncle' as a term of respect. I get theyre all close enough to refer to eachother as family though.