''My 20th birthday. My excitement grew more and more the closer I got to my friends house. We planned to celebrate my birthday there. I was expecting to chat, dance and listen to extremly loud music until the neighbors would call the police on us, with my friends. I had no idea what they had in mind to do with me.
My friends cheeringly greeted me when I came in. But I was shocked and surprised when I saw the decoration of the party room. It looked like somepony was planning a party for a foal inside a nursery. Colourful ballons everywhere, a playpen in the corner and a highchair was there.
When I asked what all that stuff was for they only said that's all for me. Then one of my friends handed me over my first present. It was pretty big and felt very light and it must be wrapped in plastic.
I opened it, no idea what to expect. And I was totaly shocked and confused when I unwrapped a package of diapers. My friends then grapped me and carried me over to a changing pad on the floor. I wasn't able to fight back because everything happened so quickly. In seconds they powered my rear end with foal powder and taped the thick white diaper around me.
Then they sat me in the higchair, gave me a red pacifier, a bib, a party hat and also a piece of cake cutted in small pieces. Then they all started to sing happy birthday for me while I was just sitting here, grumbling that I am 20 years old and not 2.
But the worst thing of all was: I had to pee really bad.''

Well, yeah. I hope you all like this picture and the small story. And no, this is not something that happened to me. (But I wish it would.)
And I am not gonna lie: I think that's the best looking diaper I have drawn so far :3.