Imagine a family of parents and 5 kids sitting at the Shabbos table and the father says - "I'm thirsty - bring me some water".
All the kids are immediately obligated in כיבוד אב D'Oraysoh and the wife is obligated to respect the husband.
It takes only one to bring the water - who would that be?
Halachicly speaking, is there an order?
Is there a precedence of the firstborn? Let the first one win? The one who's the closest to the fridge? Is there a difference between married and unmarried kids?
Is there a stealing of that Mitzvah if other is obligated more?