(Mishnah): If a man died, and left older and younger sons, the older sons do not receive extra money to buy clothing (which costs more than clothing for young sons), and the small sons do not receive extra money for their food (which costs more than food for old sons);

Rather, they divide the estate equally.

If the old sons married, the young sons also marry (this will be explained);

The small sons cannot say 'we will marry like you did'; rather, what the father gave to the old sons was a gift.

If a man died, and left old and young daughters, the old daughters do not receive extra for clothing, and the small daughters do not receive extra for food; rather, they divide equally.

If the old daughters married, the young daughters also marry;

This is a stringency of the daughters over the sons - the daughters take away part of the estate from the sons for their sustenance, but if there are only daughters, the younger ones do not take away from the older ones.

(Gemara) - Question - R. Yirmiyah to R. Zeira: If in advance of the older ones marriage, they received 100 barrels of wine for their weddings, but when they actually married, the market price of wine was high and the 100 barrels were worth 20 dinars. However, when the younger ones married, the price had gone down, with the 100 barrels being worth only 10 dinars. Do we say that the younger ones should receive 100 barrels just as the older ones did, or perhaps they should receive 20 dinars worth of wine...?

Answer (R. Zeira): They should receive 100 barrels like their sisters, even though they are not now worth as much.