She snuggles the spork because she wants to hold and protect her mommy from the problems in her life like her mommy does her. Derpy isn't quite confortable with reenforcing this (since she doesn't want her Little Muffin worrying about her), and besides her budget is a bit tight to be commissioning a doll of herself from Rarity for what may be a passing phase. The spork was provided as being a symbolic object that is as much of an outlier from the norm as she herself is.



That hat is just because she gets cold often times in the winter, and got into the habit, so now even when it is too hot to pull the covers up all the way she can't get comfortable without it.