Why coloring supplies require maximum security

The drama du jour on Friday was Ada's early-morning discovery that a mysterious perpetrator had defiled her beloved mini-notebook in the night.  The unknown criminal had used up all the pink sparkle ink in Ada's special new pen by coloring on every page but two in Ada's notebook.


There was wailing.  There were tears.  There was gnashing of teeth.


How would the doer of this heinous crime ever be brought to justice?


Perhaps we could discover clues to the identity of the guilty party in the notebook itself.  Perhaps he or she left a self-portrait!

Ok, so we could rule out police sketch artists.   

Perhaps the offender left a trademark sign, a calling card, so to speak.

Aha!  We have a suspect!  But wait...

Either the perpetrator is trying to throw us off her trail, or Ada self-inflicted this damage as an insurance scam.

Then the last piece of evidence made it all clear.

Mommy (alias "Mmommo").  Always the one you least expect.