The first thing I thought was 'could a loop be added to one corner, with Velcro or a snap, so one upper edge of the lap quilt could be attached to the back upright of one of the chair's arms?' It might make it easier to keep the quilt in place, and to retrieve it if it slips off. 20"x30" seems tiny. I'd want to be covered from my waist to my ankles/feet or at least well past my always-cold knees.