What Is It?

Here in my bed when it’s dark
There is soon
Something I hear in my room!
First I hear
The pitter-patter of little feet . . .
But then the door
Of my room opens . . . creak!
I know I should call Mom but then
I see a thing climbing up my bunk-bed ladder.
If it sees me I will be on its dinner platter!
Then I find out it’s just my brother.
Why didn’t I think that before calling my mother?