When I first get home and let Mabel out - I say for her "Oh mom, I was pretty sure you weren't ever going to come home.", and then I 'll answer and say "Of course I came home - I wouldn't leave my little girl alone". And sometimes I just do a running commentary out loud of her actions. Last night I let Mabel in from the back, and she just kept walking thru the house and pushed the front door open, and went back outside, so I said in my Mabel voice "Thanks, but I think I'll just see what is out here for a minute." Or when she can't reach something she looks at me, and I'll say "Yoohoo, can you get this for me?"
Or when she gets a toy, shows me, and then runs off - she''ll say "Look what I have, and you can't have it." And of course I have to answer when thrown that kind of challenge.:p
I mostly put a voice to what I think she is thinking and that's what makes me laugh the most.