There’s a lesser known reason why kids are told not to play with fire. Its to program their brains to think of fire as taboo, to eliminate or reduce the frequency of dreaming of fire. Children are known to react to the stimulation of dream imagery of fire. They pass piss to try to extinguish the fire. (Freud, p.62). Bedwetting is an inconvenience for laundry and related support help for the culprit.
Reference
Freud, S. (2006). The Psychology of Love. Penguin Classics: Great Britain.