Goth Family doesn't go down stairs in The Sims 2 Legacy

Hello, I bought The Sims Bundle Legacy, and I was playing with the Goth family, in The Sims 2 Legacy, until suddenly, the Sims in the house, simply (without anything stopping them), they even go up the stairs, but they can no longer go down them. I tested it on other families, and the problem is specific to the Goth family.