“What causes social anxiety in children?”

I think at age 5, it might be separation anxiety. This will take time. If it’s truely social anxiety then he will feel the same way when he is with you at the mall.

So… just a thought from what I’ve seen more commonly is that your son’s social anxiety might actually be due to separation from you. Which is more common in young kids.

Hope that helps.

See this link:
https://childmind.org/guide/social-anxiety-disorder/