Four, I think you are talking of the waistband stitching that sometimes pops on elastic waists. You must know someone with a sewing machine and some basic skill, the tread is easy to match color. It is a standard straight stitch, stretch out the elastic and match the stitch length. Clip the loose tread ends and stitch it down the original path overlapping the good area by 1/2 inch with the elastic fully stretched. It would take me about 2 minutes on my machine.