What is the ruling on the money of an employee who is absent from work while his colleagues sign for him, and he receives a salary, and what is the ruling on the food, clothes, and furniture bought with this money? And do the children bear any sin for eating, drinking, dressing, and being educated from this money?

It is not permissible for an employee to receive a salary without performing their work, as it is unlawful money. If all of your father's money is unlawful, it is not permissible for you to benefit from it except in cases of extreme necessity, and only to the extent that such necessity is removed. However, if lawful and unlawful money are mixed in your father's wealth, you are only permitted to benefit from the lawful money.