A regular needle will make larger holes in knit fabric. They might shrink back up when washed. I use a ballpoint needle for my knit diapers. Helps keep from skipping stitches or making big holes. The diapers are usually a layer of knit, a layer of knit fleece and a layer of velour. Some parts even have elastic too. So I know they will go through a quilt. I wonder if that might be an option?