According to the Peanuts Museum on Facebook, the strip below was first published on January 7, 1957⁠:

Now that’s a cute strip, but I’ve also seen the following panels out there:

I’m quite intrigued by these additions, and would love to know if they are part of the same strip, or are subsequent strips, or fan-created materials. Google and Lens have been no help.

Any ideas out there?

The Old Wolf has spoken.