Sympathies to your friends family and the loss of their precious daughter. I have grown several versions of roses with Cynthia in them for obvious reasons, and have yet to find one hardy in my zone 5. In zone 9 that's hardly a problem and the HTs with these names would probably like your zone. When I bought "Cynthia" I had it from Roses Unlimited the first time and Heirloom Roses the second time. I don't recall it on either of their lists recently but you could call and ask them. I think it's more of a pink than red as I recall, but in different climates it can look different. I know there used to be someone posting from the southeast who considered Cynthia her favorite rose. I've also tried Cynthia Brooke which I got from Rogue Valley Roses and another nursery that isn't in business any longer, but I doubt RVR has this one any more. They don't seem to stock the more unusual offerings very often. Those are the only two Cynthia roses I've been able to find.

I checked helpmefind roses for 'Cindy' roses, and it seems that the rose LeeAnn Rimes (named for the country singer) has the alternative name Cindy. It isn't remotely hardy here but it's a perfectly lovely rose that would be fine in yours. Edmunds Rose Nursery and Hortico (in Canada) are the two places in the US listed for this rose, but I don't recall it on Hortico's lists for this year and it's too late to plant bare roots in your zone. There's a Sassy Cindy miniflora rose that is listed as available from Angel Gardens, Heirloom Roses and Palatine Roses, but Palatine I'm sure doesn't have it this year. Lastly, there's apparently a Cindy Kordana rose out there that's a mini, and the Kordanas are some roses that seem to be sold in grocery stores and other big places as minis. If you can find a white mini rose with a Kordana tag in it (they frequently aren't named in grocery stores), you can justifiably call it Cindy and them it's portable to move to a spot where they'd wish to memorialize their daughter as they decide.

It's also easier to do as Flowers says and have an attribute rose as a memento. Blessed Child or Angel Face are relatively easy to find roses that would do well in your zone and they're soft colors.

Hope that helps

Cynthia