Housebreaking

From The Sims Wiki, a database for The Sims series that anyone can edit

Housebreaking is a dog skill that was added in Unleashed. Much as in Real Life, you housebreak a Sim dog by scolding it for relieving itself indoors, and praising it for relieving itself outside. Cats do not learn Housebreaking and will automatically use a litter box provided that the litter box is kept clean.