I would not pick her up just yet. They learn a lot in the first few weeks of their life from their mommy. As far as big and small dogs, you just have to make sure you train her to be mindful of your smaller pup. At a younger age they might hurt your little one on accident.When we had a bigger dog we trained him to lay down when they played so he would not step on our smaller one. So as long as you keep on eye on them they should be great friends.