Find the episode where the babies are electing their own mayor. They have a race to see if the mayor should be Tommy or Phil. When Angelica places Dil in his stroller for the finish line, she grabs a bottle of baby oil that is in the back of the stroller. She squirts it on the side that Tommy is running on so he will slip. The next shot you see that the oil is in front of Phil but when they race it is Tommy that slips in it.