My pup has been on both ends of the scale...I got him at 1.5 lb and for quite a while, he was 2-3 lbs. We put a bell on him as he was so tiny and we were scared we'd step on him (he used to 'sneak up' and sit at our heels
). He fell off a step trying to climb up and had to go to the vet as he was limping. I was really glad he started to put on weight. And out on weight. And put on weight
. He's now a healthy boisterous 6 lb jumping bean and I'm not afraid to take him for a long walk, leave him at his daycare for the day and my heart doesn't jump every time he jumps off the couch. I initially wanted him to stop at 4 lbs but I'm happy now he didn't.