In "New Friend", we see Mona doing something with her toes (presumably counting them) and after a couple seconds of that, she leans back with a huge smile on her face... and then she puts her toes in her mouth.
"Ohhhhh...nasa peepo!" Mona finding the peepo (peapods).
Mona looks so ridiculous when eating her lollipop in "Lollipop" that it's difficult not to laugh.
Anytime Mona eats is bound to be ridiculous.
Episodes
In "Snow", Mona runs outside excited about the snow, then looks at the camera and yells "IT'S COLD!!!" before running right back inside.
Russell jumping over the fence in "Over the Fence." It looks as though someone tossed him (and that was probably the case!).
Snow Person is pretty much this, due to Russell's bizarre grunting that can be interpreted as him moaning, and how he mumbles to himself when he has to put more snow.
" that it's difficult not to laugh.