9yr old anxiety

SD

My son is 9 years old. for the last few years we have battled a bit with a few emotional issues with him, and last year he started having anxiety attacks when it was time for bed. I, myself, suffer from depression and anxiety but never from such an early age.

We have him on medication, as prescribed by his Paediatrician, and he also has been to therapy previously. The medication seemed to be helping, but in the last couple of weeks he has been talking about being afraid of dying and saying things like "I don't wanna go on a plane because what if I die". I completely understand the irrational fear that comes with anxiety attacks, but I don't know how to help my son. It saddens me so much to see him going through this at such a young age. Has anyone else been through this?

P.S. He has not been abused by anyone. We have always been close. He experienced some emotional bullying from a fairly young age and is extremely sensitive but the anxiety is really becoming bad. He has started sleeping in our room because he says he wants to feel safe.