It depends on how bad it is. I had a towel with mildew that actually
stank. I washed it several times to no avail. I put it on my truck as
a rag, I still couldn't get the smell out with repeat washings. I
finally threw it away, it stank to much to even use it for a shop rag.
Try washing them & see what happens. Maybe you will do better than I.
Only bleach will kill it but enough may ruin the clothes. If its real
bad you soak each piece in bleach water then rinse and wash, if not
soaked long enough it wont work, to long clothes are ruined. First try
adding a few cups to washer load, Mold is a plant and bleach kills it by
removing it oxygen.