As for the "Smarties" bit, we give him Smarties for going potty. No matter how much we practice, it always comes out "Farty." He is being totally innocent in this pronunciation too. (Siah still refers to the act of passing gas as a "burp" or he'll sweetly say, "I have a little gas in my bottom!!)
The "Smartie" story takes a little rabbit trail... Josiah likes to name his kisses. After drinking milk he'll run up to us, proclaim, "milk kiss!" and give us a smack-a-roo. He's also been known to give: wet kisses, pretzel kisses, banana kisses, etc. Of course, I had to laugh when he ran to me yelling, "Farty kiss! Farty kiss!" and planted one right on my cheek!