First they should do things they can physically do. Once they feel good about helping and accomplishing the chore, they can switch or try others even if the chore is not ideal (and if you have more patience for it that day). This way it does not become boring and they can become better at too. In my house, I do chores during the week for simple upkeep (1-2 a day after they are in bed) and we all do chores together on Saturdays. This way, no one feels like they get the short stick or miss out on something a sibling is doing. They are younger though, so I guess this depends on age. Mine are under 6. At some point, they will have to learn they have a job to get done even when others are not. Right now, I'm just trying to associate chores with positive feelings.