I do a lot of smaller quilts - as a matter of fact, one of my favorites is 42" by 42". They are lap quilts. I am tall and I use it all the time on my chair. Most of the quilts I have made so far -- and I admit I am NOT prolific, as are some - I have made to be used as lap quilts at a nursing home. You definitely do not want lots of hang over in wheel chairs. I specifically use flannel on the backs to help keep them from sliding. Sometimes I will add an extra row to make it more rectangular, just to add length. Just remember the purpose - and don't assume there are rules. Make them for the purpose - everything can be adjusted somehow. Enjoy the process.
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