Hi and welcome. I'm fairly new to this site, as I'm a new yorkie owner. I got Hercules about 2 1/2 weeks ago and he's almost 3 months. He's weighing in at 2.2 pounds. So I can't give you any advice as to how big you should expect Mia to get. Although I've been told Hercules will probably be around 4 pounds when fully grown. But who knows!
Can't wait to see pictures of your 2 girls!!
Brandi