While the strip's characters do not age, Marvin is identified as less than 1 year old in the December 16, 1999 strip, and identified as a 2-year-old on the official website as of May 2015. The location is not explicitly defined, other than that in one strip Marvin states that he is in Indiana. However, in another strip, his mother is reading "The Sacramento Bee". In 2012, in honor of the strip's 30th anniversary, it spoofed "Back to the Future" where baby Marvin meets himself as a full-grown man. The 30-something Marvin tells his baby self what awaits for him.