Well, when I got Louie he was 16 wks old and weigthed in at a whopping 2 lbs. haha...He is now a year and weights about 5.5....6lbs on a chubby day. but I take him EVERYWHERE! I just got a new little baby girl "Bella" she is 15 wks and is 1.9 lbs..so Im curious to see how big she will get. I actually like Louie being 5.5 lbs. I was always so scared when he was smaller. It just seemed like he could brake so easily.