I think he's gonna be a biggin'. I tried this growth chart and Murphy isn't even on the chart.

At 18 months they weigh 6lbs it say. Murphy is already 7lb. 12 oz. and he was born 12-21-07
I think Alphy weighing in at 10lbs 5 ozs may be in some trouble.
http://www.yorkietalk.com/forums/gen...rt-thread.html
Actually I wen to the website as hers was much prettier and easier to follow.
Yorkie breeder site: AKC Yorkshire Terrier and yorkie puppies - Yorkie Passion