Disappearance of UC2018

In 2019, Lisa's possible predecessor, an unnamed character often referred to as 'Daughter' or 'Baby' mysteriously disappeared without a trace, spawning several theories about her disappearance.

Unnamed Character
Unnamed Character, UC or UC2018 has been Zanzalurs first proper 'doodle character', a character that has a simple enough design to be doodled frequently. Most of these kinds of characters remain unnamed due to the fact that they may not even be the same character, but multiple different characters with similar features.

Theories
There are many theories about her disappearance. Some are more mundane but others are much more compelling.

Loss of interest theory
This theory suggests that Zanzalur merely lost interest in UC2018 and decided to move on, its a fairly simple theory, yet it has a few problems.

UC2018 has a fairly simple and appealing design, and there should really be no reason to abandon her.

Evolution theory
The Evolution theory suggest that UC2018 evolved into a different character, and that the character referred to as 'Baby' is Lisa all along.

The problem with this theory is that Lisa has a completely different origin story than UC2018 and are separate characters. Another problem is that Lisa is not a doodle character, Zanzalur never 'doodled' Lisa as much as UC2018 due to the more specific character design.

Hidden under the radar theory
This theory suggest that UC2018 is still there, but Zanzalur only draws her traditionally, which usually leads to the character not being shown to the public. This theory may be true, although when Zanzalur draws something traditionally, said drawing often leaves a trace in the digital world.

Assassination theory
this theory suggest that Lisa may have assassinated UC2018 in order to take over her role as main OC. While the current spokesperson of the Zanzaverse, Penny believes in this theory, there is no real evidence to support it.