Happy Birthday Lexi!
Two does seem to come before you know it! It's a bitter-sweet moment for us yorkie-moms!
Here's a link to a cake recipe. I think it's the one Simon and Hallie's mom made for Simon, but not sure I've got that right. You might want to check with her!
http://www.ljcfyi.com/ljcsProjects/cooking/dogCake.html
Good luck!