The internet is a strange place sometimes, as proven by “Arthur and D.W.,” which was one of the top-trending Twitter topics Thursday. Arthur and D.W. are cartoon characters from the PBS kids’ show “Arthur.”

For some reason, people were making incestuous jokes about D.W. and Arthur, who are brother and sister on the show. It’s not clear why this trend started, but people were having fun with it Thursday morning.

For those who aren’t familiar with the TV series, which is named after its main character, Arthur, it’s set in a fictional place, Elwood City. It follows the life of 8-year-old Arthur Read, who is an aardvark. The third grader attends Lakewood Elementary School.

He has two younger sisters: D.W. and Kate. D.W.’s name stands for Dora Winifred and she’s 4 years old. Kate’s age is never revealed but she’s always presented as a baby. The family also has a dog, who is named Pal.

Even though it’s a kid show, D.W. is a favorite character among adults because of her sassy attitude. She is confident and dramatic.

Above all, it’s not clear why or how this trend got started. It seems people just had a major case of nostalgia Thursday morning. The PBS show first started to run in 1996. It’s still on TV today. Season 19 is currently airing on PBS.

Some of the posts people tweeted have been shared below: 

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