Sounds like they have very different personalities and tolerance to stress. They were probably born that way. I suggest making sure there are plenty of tiny crickets for them, with a little food for the crickets as well so uneaten ones don’t get hungry and chew on your babies. Then cover the front of their habitat with a sheet or towel. If you cover the whole thing, the temperatures might get too high and ventilation could become an issue. Then do not put your hand inside for two weeks, except to change the water dish and add more food as needed. That should give your shy one enough time to destress and begin to eat and calm down. Being that patient may seem maddening when you want to force him/her to eat and interact, but it will pay off in the long run.