Do sons married from land their father designated for marrying off their younger siblings inherit, and do those for whom it was designated inherit from it if the married ones bore their own marriage expenses, and do daughters inherit from this land?

It appears that the father bequeathed the land to his young children to help them with the costs of marriage. This bequest is invalid, based on the Prophet’s (PBUH) saying: "There is no bequest for an heir," unless the adult, mature heirs approve it.

If all of you approve the bequest, the land will be divided among your younger siblings. If some of you approve it but others do not, the bequest will be executed only from the share of those who approved it. If you do not approve the bequest, the land will be added to the inheritance, and the entire estate will be divided among all heirs (males and females), with the male receiving the share of two females. Your case involves seventeen parts.

The fact that the older siblings covered the marriage expenses for their younger brothers does not affect the ruling. If it was a donation, then there is no claim for it. If it was a loan, then they have the right to claim it when it becomes due.