If one disposes of a lost animal by selling it, does he return its value or its equivalent?

Question: My father bought a camel thirty years ago, which was originally a found animal, and sold it for eight thousand riyals. He then bought a camel for seven thousand riyals with that amount. He is confused about the camel he bought in place of the previous one, and the last camel has produced offspring. Does he return the value, or the camel and its offspring, or what?

Answer: They must return the money to the owner of the camel if they find him and know him, because they erred in selling it. If they do not find him, they should give charity with the value of the camel, the eight thousand riyals, on behalf of its owner, and that is sufficient. As for the camel he bought last, which has produced offspring, he keeps it; it is his camel.