Jace decided he loved Madison's new soccer ball. If you tried to take it away he would try to grab it will his feet.
He then tried to figure out how to crawl with the ball so he wouldn't leave it behind. The results him crawling over it and picking it up with his feet and bring it back to his hands. His feet are like an extra set of hands. It is quite bizarre to watch him figure out ways to pick up things with his feet.