What a beautiful pup!!  Princess Sophie is a few weeks behind your pup but she sure does look a lot like him. LOL  She will get weighed again next week when she gets her stitches from her spay out I think she should be about 5 lbs.  She will be 7 months old on the 4th of July!  YeeHee  Of course, I think she's perfect and I bet you know yours is as well!!  They are just wonderful!!  
