Because Iris spent most of the time sleeping, since she was still recovering from traumatic birth experience, Grace suggested to alternate between giving the baby breast milk and her concoction, since they had to maintain the baby's health, giving Rora only breast milk wouldn't be enough.
Therefore, unless it was time for Iris to breastfeed her baby, Rora would be with Cane. She would sleep on her crib in his study room, under Cane's watch. He would go every now and then to bring her to Iris and waked her up.
The alpha literally didn't trust anyone to be near his daughter, if it was not an urgent matter that he had to leave Rora, he would be seen with the baby all the time and even if he had to leave, there would be Jace or Ethan by her side and a few more warriors nearby.