I agree that there are some very strange sized patterns available. I would think something that is 42 inches square would be a wall hanging. If I wanted to make it into a bed sized quilt, I could make 4 times as many blocks--ouch! I'd have to love that block to pieces, to make that many--or I could double the size of the block. If the original is a 6 inch block, it should be quite easy to make it into a 12 inch block.
I have resized many a pattern in my quilting days--and not always bigger either. To me, that is part of the fun--making the pattern my own.