My beloved quilt was found by my sweet bored puppy, and thus, many holes ensued.
First, I noticed the batting in my quilt was twice as thick as the all-cotton batting I have on hand. I cut a piece twice as long and folded it over. Then I carefully stitched it to the existing batting.
Next I took a square of all cotton fabric that was bigger than the hole I was trying to repair. I folded it under about a quarter of an inch all the way around and stitched it in place.
Last, I quilted through all fabrics using a similar pattern as the rest of the quilt to ensure sturdiness and continuity.