Must I give my siblings their share of the profits previously earned from trading in alcohol, considering that they demanded it after I ceased this activity and after they had previously relinquished it?

If your adult, sane siblings have in writing relinquished their claim to the money, then they have no right to it. The money in your possession is of two types:

1. What your father used to start the business: If its source was permissible: It belongs to you alone after your siblings' relinquishment. If its source was unlawful: It must be spent on charitable causes, such as the poor and the needy. You may take from it what you need if you are among them until you acquire lawful earnings, and then you dispose of the remainder.

2. Money resulting from trading in alcohol: It must be disposed of. You may take from it as previously mentioned.