Keep in mind, too, Mary,
Bostons quilt is using a very common theme and how many uinique pumpkins are there, or fences, etc.. just like quilt blocks....
They are very common and have been around for a long time.. and most are in the public domain... You are not going to have a problem drafting your own version of a common (and sometimes not so common) quilt block.
You aren't even going to have a problem reproducing a quilt layout, border, sashing, etc. They are way to common to be considered someones unique work..
Go create and have fun and don't worry.. and be considerate of other peoples' work.. If you want to make a tracing or otherwise reproduce someones drawings, ask them...and give them credit..
You will feel very good to say "I was inspired by xxx and I have permission from the artist to use their image"