I made a quilt with appliqued butterflies on it back in the early 70s. I have made to two quilt a couple of years ago with butterfly fabric. I still have 4-5 yds of a lavender background W/ butterflies of different colors, I plan to make a quilt with it one day.
Butterflies are a sign of "NEW BEGINNINGS" so I especially like them in a quilt for someone going through a tough time. Besides, they're colorful and make me happy. Ditto dragonflies.
Butterflies are coming back in vogue again. My MIL loves butterflies and has been getting a few pendants from the local jeweler as estate pieces. I have a quilt kit I bought for her. I've finished piecing it and now I need to quilt it.
I think since the I Spy quilts came out, any insect goes! I do have several pieces of fabric with some gorgeous butterflies on them.