1. Be sure to register as a small batch manufacturer.
2. There are two different tags required for kid's items - FTC and CPSC. The FTC are the care and content labels. CPSC are tracking labels that look very much like brand labels, oftentimes.
3. I've seen no definitive info on whether *or not* you can use one tag for both FTC and CPSC labels.
Fabrics are on the exempt list for testing, I believe. They are not exempt from needing care/content tags. And as far as unknown fibers go, I *believe* you can state something like "fiber content unknown". This is a frequent question for those using recycled fabrics.
All this is to the best of my knowledge and is by no means authoritative. But I wanted to bump this up. I'll let the real experts answer the rest, and correct any incorrect info I may have included.