You must have taken that first pic right after he got done playing: he's got the Devil in his eyes

- full of mischief! As far as I've been able to tell, that's pretty much standard for a Yorkie
Multiple dogs are like multiple kids: you don't stop loving the first when the second comes along - your heart just kinda expands to accept and love them all. It's the same as when you get a new pup after a beloved furbaby has departed: you're not replacing your old friend - your heart just builds more room for the love and memories the new pup will create
Besides, the more they play and exercise each other, the less YOU have to do
Enjoy!