1.
Feeling jealous is painful. Feeling jealous and then being shamed or punished is confusing for a child. And it doesn't equip them to know what to do with the feeling.
When your child feels jealous they need the same set of things they need when they feel any other painful emotion.
1. Empathy and support understanding their emotion and learning words to put to it.
2. Help regulating their body.
3. Compassionate guidance on how to cope with the feeling.
Jealousy is not a character defect. It's a normal and complex body state that abates when it is acknowledged and the person feeling it is given emotional support to handle it and not act it out.
The idea of toughening up your children to deal with the world only makes you their first bully, stripping them of their sense of belonging with you; treat your children with respect and connection so that they instinctively protect themselves from unkind and cruel treatment.
Model for them your own consent process, and help them deeply understand the nuance of desire
The difference between consequences and punishment is important to understand, as consequences are the natural outcome of an action and necessary for learning, while punishments are intentional pain inflicted to control behavior, which can damage the parent-child relationship and hinder a child's growth towards internal security.