Scroll down to the section for the pet you unpacked, and edit it to add # --~~~~ below the other users' signatures. Do this once for every minipet you found (i.e. if you found two, add the line twice).
Tip: You can avoid scrolling to the section if you click on the text link for the minipet in the tally table - that will take you there.
You can then update the statistics by editing the tally. The numbers in the tally must match the number of signatures in the corresponding automatically numbered drop lists. When you've got the numbers done, use the preview to get the new TOTAL SUM computed for you, and enter that on the TOTAL SUM line. Done!
For the result to be statistically valid, please decide first if you are going to update, and then open your presents. Not doing so may introduce a bias.