Is there any way to soften kids bed sheets?

My 4 year old son got a set of motorcycle print sheets. I know they are not a high quality material. He loves them, but says they hurt his skin. I've washed them several times.Is there any way to soften kids bed sheets?
You know what works really well...wash them in REALLY hot water with a lot of fabric softener, and when I say a lot I mean A LOT! Just add the extra rinse cycle at the end so that it doesn't irritate his skin and then dry it on high heat...they will be so soft he will never let them go.Is there any way to soften kids bed sheets?
Have you tried putting them in the tumble dryer before putting them on his bed? Or you could buy some cot (crib) sheets and put them on the bottom half of his bed so he'll be sleeping on that but he'll be able to see his beloved cars on the top of the bed.
tried fabric softener?
Beat them on a rock down at the river.
Easy recipe for fabric softener-- maybe this will help. Use 2 cups baking soda, and add distilled water until it forms a think paste. Add to the paste some antibacterial essential oils (tea tree, lavendar, pine needle, etc). Pour the paste into paper muffin cups (this recipe makes about 12 muffin cups). Let harden overnight. When ready to use, crumble one disk into the rinse cycle. It gets rid of hard water and makes the laundry smell great.
A liquid fabric softener and lots of Bounce sheets in the dryer will help a little. The higher the thread count on the sheets, the softer they'll be. If the softeners don't help, try and exchange the sheets for some with a higher thread count. My sheet have a threat count of 500 and they're sooooo soft. Hope this helps.
Fabric Softener?
Try Bounce fabric softener dryer sheets. They have an unscented kind. I use them on my daughter's sheets all them time.
I use 1/2 cup of vinegar in the rinse cycle, then rinse again with milk powder to remove all the soap, hang to dry, finally fluff in dryer for 5-10 minutes.
Use any fabric softener (like Snuggle). Add it to the final wash cycle. However, for children, you might look for 7th Generation organic product. Some kids are very sensitive chemical softeners. Also, printed sheets are hardened by the chemical/plastic paints. If all else fails, you should chose 100% cotton sheets in blue, green or yellow. Or even plain-old white.





Designs that are WEAVED into the fabric are also much softer than superficial paints. (I'm a painter and ceramist.)
Have you ever used Dreft detergent? A good fabric sofner is always good. I personally perfer liquid over sheets. Bounce, Purex and Snuggles are pretty good brands of fabric softner.