Everyone is right about earning their trust, it does make it harder that you are not there with them all the time.
I have had a few incidents with unruly kids chasing my birds, but when I go out to stop the nonsense, my birds come running to me for safety.....I AM the crazy chicken lady, and my birds are so spoiled they should smell bad,LOL!
Try the melons, watermelon works wonders for shmoosing birds, they LOOOOVE it!
Take a few halved watermelons out there, set them out, and set nearby, still and calm and wait to see if they come for them.
It is going to take time to earn their trust back.
They say that chickens have small brains and have short memory spans....this proves that theory all wrong.
I have a roo that my daughter likes to tease, and he will run from her.....however, 3 days later when she goes in the coop to get eggs, he waits, and he will corner her in the coop and have his revenge....with me standing outside snickering for a few moments, before going in to "rescue" her.
This sounds mean, but he wont hurt her, just scares her, like she scared him, LOL.
Chickens are "routine" animals, now they have to get back in the routine of normalcy after the demon child broke that pattern...even if it was one moment, they remember.