It was implied. What do married couples do? And given that she has no choice in the matter of marrying you, why should we assume you shall give her the choice in other things?
I dont think people care whether that was how OTHER tribes in ancient times did it, but since we players have different (probably more advanced) emotions and more intelligence than what they ahd back then, i dont think you will get away with it in this tribe. Even if the chief doesnt stop you, we will (or at least I will, not sure about others).