Did the father do wrong by dividing the shop and capital between only two of his sons, knowing that these sons invested the money until it multiplied and they got married from it?

The authoritative fatwa dictates the obligation of equality among children in gifts and endowments, unless circumstances necessitate preferring one of them due to a need. The children's work in their father's wealth does not justify preferring them in giving, and they are entitled to wages for their labor, unless they agreed with him to divide the profit, in which case they receive what they agreed upon. Otherwise, the yield belongs to the father, and the children are entitled to wages for their labor after deducting their expenses and marriage costs.