Is the sale void, and does the third brother have the right of pre-emption over his brothers' shares that were sold after the death of one of the apartment's shareholders?

The brother has the right of pre-emption (shufa'a) over the share of his two brothers who are partners with him in the apartment. Pre-emption means that a partner takes what his co-partner has sold for the same price, obligating the seller. This is supported by the words of the Messenger of Allah, peace and blessings be upon him: "Whoever has a partner in a plot of land or date palms, he is not to sell until he informs his partner. If the partner agrees, he takes it; if he dislikes it, he leaves it." And his saying: "The Messenger of Allah, peace and blessings be upon him, ruled with pre-emption in everything that has not been divided. But once boundaries are set and roads are laid out, there is no pre-emption." Therefore, the brother's claim is valid unless he agrees to what has transpired. Reconciliation and forgiveness are advised.