Headcanon

[middle_strings]

Daily Life
♠ Of the three sand siblings, Kankuro is the only one who can cook without some sort of kitchen disaster.
♠ While not overtly religious Kankuro has picked up the odd habit of swearing by the name of the first shinobi-puppeteer, Monzaemon Chikamatsu. At least in his head.

Skills
♠ Kankuro can make complex bead sun-catchers with great skill. He learned due to boredom after getting hurt on a mission.
♠ Has fairly good drawing skills but only really uses them to design puppets.
♠ Can and has made simpler puppets, the kind used by children, as a way to practice his skills. That they end up at the orphanages around Suna, is really no ones business.
♠ Has perfect artful calligraphy and beautiful handwriting.
♠ While Kankuro normally talks rough, he can and will use polite and flowery language to put an oppenent off, or if he really wants to mess with people's heads.
♠ Is self taught in puppetry arts [This headcanon may be refuted with later canon evidence, but by my best dissection of what is given, this seems to be the more likely]

Past
♠ Once, just after Kankuro turned twelve he was asked to assassinate his brother. Allowed to refuse the mission he did so, but that one moment changed his slightly distance father into the Kazekage he dislikes so passionately. The only thing he is grateful for, once he became old enough to calmly analyze that memory, is that his father offered him the choice to refuse instead of enforcing the decision as Kazekage. It is that gratitude and his other okay memories of his father that leave him conflicted as to how he feels about his father.
No one know about this offer. Not even Temari or Baki or Gaara. Kankuro is glad to keep it that way.