Parker and Nixie were having a great time together ever since Nixie turned herself into a baby. It was past their bedtime, but the two little diaperbutts went to the kitchen to get some snacks for a late night movie. Parker found a strange canned drink that he decided to try. Nixie noticed this and tried to stop him, but it was too late, Parker drank it. Parker felt strange things in his body and he noticed that Nixie got further away and his pelenka became very tight. He turned into an adult. The canned drink was actually a serum Nixie made to cure herself of her baby form. The Serum was only temporary, thankfully, and Parker soon returned to his adorable baby self, in need of a new diaper that wasn't stretched out.
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Angellothefox
This kind of reminds me when spike got a hording habbit and turned into a teenager. It is the same look that parker has.