Over the course of adolescence, relationships among siblings become more egalitarian but distant and emotionally intense.

more, less

Explanation:

After childhood and during adolescence, siblings become less emotionally attached and more distant as they seek more independence in this time. There is less emotional conflict and close companionship among siblings as their relationships become less emotionally intense. This is because during this time they seek out more independence and explore social interactions and friendships outside.

fertile good for trade etc