How old are these children?
I can imagine a child say under 12 feeling ‘neglected’ and going to auntie to complain that 'when so-and-so is over my cousin isn’t as interested in ME", and I can imagine that aunt, and aunt’s sister or brother (parent of cousin feeling neglected) and aunt’s child all getting together to talk about how family and friends aren’t in opposition to each other. . .
if the kid is a teen and coming to complain to auntie, I think that auntie might say, “Talk to my son and work it out between the two of you”. . .