Those interested in collecting inheritable traits could use daughters to help through strategic marriages, as well.
Marriage
Just as in old times, you can marry your daughters to foreign families to create alliances. In CK3, there are a few other reasons to marry depending on which type of marriage you choose.
Normal Marriage – Alliances
The main reason for marrying off your daughters is to secure powerful alliances with other rulers. Allies can be called during war and will fight alongside you. In a normal marriage, children are from the father’s dynasty. While this means you won’t be able to inherit through your daughters, it’s easier for other characters to agree to the marriage.
Matrilineal Marriage – Alliances and Inheritance
This type of marriage allows children to inherit the mother’s dynasty. In this way, you can inherit through your daughters. Matrilineal marriage is necessary for those playing as women or those with no sons. Otherwise, you won’t have any dynastic heirs, and the game will end. Of course, matrilineal marriages can be used to secure alliances, too. However, it’s sometimes impossible to get other rulers to agree to the marriage if their son is an heir. Rulers will often let you matrilineally marry their second or third heir, so if your neighbors have enough children, you still have a chance at an alliance. Tip: If you matrilineally marry your dynasty member to a secondary heir in another realm, you can murder the heirs before them. Then, after two generations, your dynasty will rule!
Councilors
Your daughters can often be assigned to your council, depending on your religion. Some players will be able to assign daughters as Spymasters only, and others will be free to place daughters in other positions. This is useful if you have a very strong dynasty with high attributes, since they’ll be more effective than other candidates. The Coterie dynasty perk tree also buffs your family members further, making them even more powerful as councilors. This tree is from the Iberia DLC and is only available for Iberian heritages or those with realm capitals in Iberia. Beware of opinion debuffs from powerful vassals who want council seats! Reserving them all for family can make vassal management harder.
Shieldmaidens & Knights
In some cultures and religions, you can make high-prowess women from your family into shieldmaidens. This allows them to serve as knights, just like men. Depending on your religion, all women may be able to become knights by default. This is especially useful if your heirs are male. You don’t need to risk their lives in battle, and can instead raise your daughters as powerful knights.
Vassals
Most of the time, women can become vassals in CK3. This is usually caused by succession when there are no male candidates left in the dynasty. If succession is set to “Male Only,” this is never possible. However, with the correct laws, you can also grant women titles freely. You can make your daughters vassals with this law.
Refining Your Bloodline
You can use daughters to breed good traits into your dynasty, like Beautiful or Herculean. This is achieved by marrying them to a man with one of these traits, preferably one or more that your daughter does not have. Their children might inherit good traits from both parents. In this case, you can keep marrying these children to other characters, adding more traits or strengthening them. Once you have characters with good traits, marry them back into your main line when possible. Ideally you have focused on one trait in your main line, and a different trait in your daughter’s line. Using this technique, you can focus on several inheritable traits at once. This reduces the number of generations you’d spend collecting traits! Of course, extra sons can be used for this technique as well.