Rugrats

Lil's Phil of Trash (8x41)

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Taffy takes the Rugrats to the local park. While there, Dusty, a boy that Taffy meets at a park, shows Phil how to pick up trash. Afterwards, it becomes so serious to Phil, that practically anything can be trash, much to the ire of Lil. Meanwhile, Taffy starts to fall in love with Dusty, due to his environmential consciousness -- that is, until she learns the real reason why Dusty is picking up the litter.