What are you scared of?

In many things my boys are the same - especially because No. 2 copies and mimics No. 1. In their fears they are very different, as I discovered today. No 2. son was sitting on the carpet doing puzzles when a huge spider lumbered towards him. He whimpered and shied away. I whacked it with a magazine. Sorry. No. 1 son would have picked it up and carried it out of the door. But No. 1 son is scared of the dark, he insists on a light being left on and in his nighttime vision, bags of toys metamorphose into scary monsters. I'm scared of the cliche - how would I cope if I lost one of them?