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Give him a fly swatter and have him keep count of how many he can kill? Make it a game with a prize? Is that too violent?

Hahaah smart idea! I’ll have to see if I can find one. Will see if he can overcome his anxiety

You will have to convince him not to be scared, he is still tender and you have the opportunity now to change his mindset.

Will try. I even sprayed them for him but they aren’t dead so he keeps watching them and scared to go close

I understand his fear, the pains from the bite.

They’re not painful flies but apparently they kept going into his ears yesterday

Oh okay.
Now I understand.

I don't think it's going to be hard to convince him.

Maybe he watched someone getting angry about the flies and chasing/hunting them away?