Because why not?
So I pretty much have this AU in my head, where the developers for Sugar Rush Speedway wanted to give Vanellope von Schweetz a more sensible age/design for her princess stature, because why would a 12 year old be in charge of a kingdom? And the events that occurred in the movie pretty much happens the same way.
These two look so cute though.
EDIT: I guess I forgot to mention what's going on in this pic. It's Ralph, as the Best Man, escorting Vanellope, as the Maid of Honor, at a certain wedding that was shown in the movie.