In which way was the serf different from the slave?
Serfs could pass on their inheritances to their children and slaves could not.
A serf was not a property. They did not belong to a person. Their job was to work the land. However, a slave was seen as a property and could be owned by an individual. Taking this into consideration we can say that serfs got paid for their works and the money they received and the goods they had could be passed to their children on their inheritance.
Serfs could pass on their inheritances.
Serfs were not slaves. They weren't commonly treated as a property and basically, had to work on the Lord's land. Although many had fewer rights than a freeman, they still had more rights than slaves. Inheritance being one of them.