Football season in over for the moment so I have no particular complaint with your toddler wearing the black jersey. (Had the jersey featured green birds or silver and blue people, I may have considered reporting you for child endangerment.) However, if you are going to be foolish enough to dress your child in a black jersey on one of the first steaming hot days of the year, please do your child a favor and don't tuck the jersey into his shorts. From both a ventilation and a fashion standpoint, I find that quite cruel.
Burgundy Jerseys are Cooler Anyway.