The actress, who is married to Will Kopelman, also has a one and half year-old daughter named Olive.
Drew has expressed her delight that the two girls are so close in age, saying: "Olive is a year and a half now so [the girls] will be close together in age ... I think, just get it done - it will be awesome!"
Drew also opened up about how her own difficult childhood has impacted her thoughts on motherhood, saying: "My parents split up before I was born and my dad was just never capable of being a father. It's something I really accepted and became okay with early on. But it's shocking to me that someone can make that choice. As much as I accepted it with him, I could never accept it in a partner ... for some people showing up is just not possible and that is incredibly frustrating. When you become a parent, and think about what kids need, it is very emotional."
Drew went on to say how she loves being a mum and has a very hands-on approach: "We spend every weekend together. It's just us. I can't wait to see how that's going to work with the second one!"