There are some really tiny Yorkies out there. My friend in Hawaii has three, two of whom are fully grown and weigh less than 3 lbs. They are tiny but perfectly formed, so it may be that your little one is going to be a "tiny" too. There are some great fresh food recipes on this website, although I know that IAMS is a good brand, I prefer to feed fresh food. That way you get no preservatives or artificial colours. Keep up the good work and I wouldn't worry too much if she is eating well and keeping happy and her stool is normal.