I've heard of fans rushing the field after a big win, but I don't think I've ever seen a family member celebrate a touchdown on the field ... in the middle of a game. 

Western Michigan beat Buffalo 71-68 in a wild seven-overtime game. Turns out, though, the twists and turns weren't limited to the scoring. During the first overtime, Western Michigan tight end Donnie Ernsberger scored on a 14-yard touchdown pass. But afterward, Ernsberger's sister ran on to the field to celebrate the score. The problem? The game wasn't over. Western Michigan pulled to within one point of Buffalo (38-37), but still needed to kick the extra point to tie the game and send it to another overtime. 

The celebration netted a penalty assessed on the extra point. Had that been missed, family dinners in the Ernsberger household may have been awkward. They still might be.