Does the father have a share in the land of his deceased wife, which she equally divided between her two sons before her death, especially after he inherited a portion of her wealth, refused to pay her debt, left her and her two sons for ten years without maintenance, and declared his desire to inherit from his sick wife?

The land you mentioned your mother sold to you and your brother before her passing is one of two scenarios: either it was a gift in the form of a sale, or a real sale. If it was a gift and the children did not take possession of it until after the mother's death, then it is a bequest to an heir, and it is not enforceable unless the rest of the heirs agree to it. If it was a true and valid sale, then it belongs to you, and the husband has no right to it.

As for what you mentioned about your father refusing to repay the debt from the inheritance, you are permitted to deduct a quarter of the debt from his share. And what you mentioned about his abandoning you and not providing financial support, if proven, then what the wife spent on herself and her two children must be deducted from his share. These disputes should be brought before the Sharia court.

If the mother passes away leaving behind a husband and two sons, the husband inherits a quarter due to the existence of a lineal descendant, and the remainder goes to the two sons by ta'sib (residuary heirship), with the male receiving the share of two females. The inheritance is divided into eight shares: the husband receives two shares, and each son receives three shares.

Finally, it must be noted that matters of inheritance are highly complex and sensitive, and a mere fatwa is not sufficient; rather, the matter must be brought before the Sharia courts for investigation into all aspects related to the estate, heirs, debts, and bequests.