I've decided to pay him some extra money for helping out with the house chores.
「普段、我が家のチビ助には家事の手伝いは無報酬でやってもらってます(めちゃくちゃ文句たれますけど)。しかしチビ助にどうしても欲しい物ができたとのことで交渉の結果、少々大変な家事をこなしたら、いくらかお駄賃を払い、それを貯めて買わせることになりました。」
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"Usually, we ask our Chibisuke to help us with the house chores, but for free. (He complains a lot about this.) But since Chibisuke has something that he really wants to buy, we've done some negotiations, and decided that if he helps out with some more difficult house chores, we will pay him a bit of money, and he can save that up to buy what he wants to get."