Weird dream from when I was 9? What does it mean?

I was at the house I used to live at, and my brothers were in the basement playing with a "remote" tarantula. Then it came upstairs really fast. I was really scared for a second while my sister was just standing there looking at it! Then for some reason, the doorbell rang and it was my sister's ex-best friend. She wanted to know if I'd buy an animal encyclopedia (I was obsessed with animals when I had this dream) and I wanted one but my mom said, "That's what Wikipedia and the internet are for." (By the way, I had no idea what Wikipedia was, I was only 9 when I had this dream) So I took a step where she was and she was gone, then I walked a couple of steps down our sidewalk (on the left is a big flowerbed) and there was my same sister digging a foot-deep hole right underneath a tree where there were no flowers. I asked her what she was doing, and there was a tornado right about to hit our house (which i had known about before - and i was SOOOOO scared of tornadoes since i had been in one at 5) and she said, "I'm trying to take shelter from the tornado."