because diffrent companies make diffrent size mattresses or diffrent size bunk beds

If the springs in your mattress (or mattresses) are squeeking, there is no remedy short of getting new mattresses.

mango

A bunk bed is a bed that are the same size on top of another, with a few steps to reach the top bed, they are typically used for young people as they may share a bedroom. The mattresses on these beds tend to be the same size.

Katy Superior Fully Bound, British Superior Deluxe Sprung Cot Bed Mattress and Cosatto Springi Cot Bed Mattress are all examples of some bed mattresses that are suitable for toddlers.