Hi everyone! In an attempt to make my life more sane, I think we are going to have my daughter's private dance teacher help her with front walkovers for a bit before re-enrolling in a class. She runs a very small studio, so she does not have mats. She suggested purchasing an octagon mat, which I can bring to her studio. My dilemma is that my daughter is likely between a Medium sized octagon and a Large. My daughter is average in height for her age, and she is 8 going on 9 in December. My worry is that she'd outgrow the Medium (or might have already) but that the Large would be too tall. If a child is borderline, it is better to go up a size?