One of the best episodes! 

But it still pisses me off that Grandpare just abandoned his daughter for the rest of her life. They forgave that awfully fast,

Why did Granny Smith go to wash up in the outhouse? 

And when they were shocked to learn their mom was a Pear Goldie said a jar of pear butter looks like a jar of apple butter. So they knew their dad was an Apple. Did they think their mom was too?