Help: Identify new-to-me symbol.
 

I just recently started working with a family who has a newborn that was not supposed to survive to term, much less be alive for the past... 2 weeks, now, I think. When we went to their lovely home, I noticed a red silk square hanging over their door. I didn't want to be rude and ask them, but I'm curious. I've googled the hell out of it and can't figure it out.

They are an African-American family, the silk square is brilliant red and hung from one corner (so it's almost diamond shape) by a tack in the center of the doorjamb above the front door. It's been there for a little time because the edges are frayed, unless that's how it's supposed to look, because it's not faded at all. The house faces almost due north from the front door, I don't know if that makes a difference. When they found out the child's diagnosis in May (in utero) there was no hope at all, so they weren't praying for her at this point. They've mentioned faith several times but no specific deity and mother's family lives in South Carolina.
I'm stumped, anyone have any thoughts?

(I'm going to ask on Friday if I haven't figured it out by then)

I wonder if this has anything to do with it - Read the middle section on the Bunu

Cloth that does not die: the meaning of cloth in Bunu social life. - Free Online Library