Bert el Stick was a Spanish sexist stick that puppeteered the troll in Trolls these days.
In Day 6 of The 12 Days of Chris & Jack, Chris and Jack recounted a classic holiday story about a sexist father, his son, and a magical Christmas tree. It is theorised that this is the origin story of Bert el Stick, a stick imbued with the spirit of the tree and the water.
Biography
In the forest on a winter night, a father and son chopped down a tree to place in their home. When the son tried to dress the tree with a little tree skirt, the father shouted with prominent misogyny.
"AIN'T NO SKIRTS ON MY TREE! YEAH! I... HAVE... ISSUES... WITH WOMEN!" — the father
Later in the night, the son secretly placed the skirt around the tree. By the next morning, the tree had withered due to the stale water.
"I only wanted to prolong its life." — the son
"No you put a f***ing skirt on it." — the father
To both the father and son's delight, the spirit of the tree and the water rose from the remains of the tree and restored it to health. (THE STORY OF THE TRIMMING OF THE TREE WATER)
"I FIX IT ALL!" — the spirit of the tree and the water
Some time after these events, the tree, now sentient through the spirit of the tree and the water, adopted misogynistic traits from the father. Eventually, the tree splintered into pieces. From its remains, a large stick found its way to the Barleydale Bridge and magically took over the cerebral cortex and motor system of a troll, who would begin to tell stories of fathers and sons to hikers attempting to cross the bridge, whilst being super sexist.
It attacked Chris W. Smith's groin. (Trolls these days deleted scenes, 4:33)