My 1 1/2 year old and I are going to be Despicable Me minions.
yellow hooded sweatshirt, blue overalls, stitch on a felt “G”, yarn or pipe cleaners for hair on the hoodie, a pair of goggles (or those round black costume glasses you usually see in costume stores), and black gloves. Since my kid won’t keep the goggles on, I plan on drawing them on him with eyeliner.
Carbon Costume is a great resource for duplicating a character’s look. Gives you a list of currently purchasable items to get you most of the way there.
Does not cover make-up.