Tom, I think I can now answer my (admittedly pretty dumb) question. I make reference to the following
which includes the following sentence.
Each person, couple relationship, and parent-child relationship can have up to 1,000 sources.
I'm particular interested in sources for parent-child relationships - exactly how such a source would be entered into FSFT, and then how it would be moved to RM.
Here is an example which I think ought to qualify as a source for a parent-child relationship in FSFT. A death certificate typically includes the names of the parents of the deceased when those names are known by the informant for the death certificate. That seems like a Child-Parent relationship to me.
Suppose there is a death certificate in FSFT for an individual, and suppose that individual and his or her parents are already in FSFT. Suppose there is a record hint in FSFT for the death certificate (or equivalently, a WebHint in RM), and suppose I confirm the record hint. There will be three confirmations, one for the deceased and one for each of the parents. I believe it is the confirmations for the parents that FSFT could be calling a "source for a parent-child relationship". So far so good, unless I do not understand what a "source for a parent-child relationship" is in FSFT.
Further suppose that I have the same three people in my RM database and they are appropriately "matched" using the FSFT API. So I click on the FSFT icon in RM for any one of the three people, and then click on sources (I'm still in RM, not in FSFT). For the deceased, I will find the death certificate tagged to the name, gender, death, and birth. For either of the parents, I will find the death certificate tagged to the name and gender. But nowhere will I find the death certificate tagged to anything called "parent-child relationship", even though that's what the source is attached to in FSFT (or at least so it seems to me).
So let's go back to FSFT. From the User's Guide, I find the following sentence.
Or if the source is attached to a parent-child relationship, hover your mouse cursor over the child’s name. Click the Edit Relationship link that appears.
The screen doesn't say Edit Relationship, but it does say Edit Parents, which I think means the same thing. Indeed, sort of a "Relationship Screen" comes up if I click on Edit Parents even though the screen doesn't really have a title. There are a bunch of boxes, including one for sources. But the death certificate I have not already confirmed is not listed for the person I'm looking at, and indeed it appears that there are no relationship sources at this point. So my theory that attaching the death certificate as I described would create a parent-child relationship apparently is not correct.
Let's try to add a parent-child relationship anyway in FSFT, so I click on New Source from the relationship screen. A screen comes up asking me to give a name for the source and a URL. Since I happen to have the death certificate in question posted on my own Web site, I provide that URL. I answer a bunch of other questions, and it seems to take the source.
So now I go back to RM, and for each of the three individuals I click on the FSFT icon and then click the Sources tab. For all three of the people, it is the case that my newly added source is not visible on RM. Indeed, my newly added source does not appear in the "list of sources" screen on FSFT, either. The only place my newly added relationship source seems to show up is on the aforementioned "Edit Parents" screen, the place where I entered the information in the first place.
So the answer to my question appears to be (unless I'm still doing something wrong or still not understanding correctly) is that sources for parent-child relationships in FSFT are not visible in RM, and they really are not even visible in FSFT, either, except in the most indirect and hard to find way. Perhaps this is an area where FSFT plans some enhancements in the future, but it appears to me that right now the feature for sources for Parent-Child relationships is implemented so incompletely that it might as well not even be there. Maybe I'm wrong, and I hope I am. But that's the way it appears.
Sorry to have been so fuzzy with my question. I clearly didn't quite understand what I was asking. I'm still not sure that I do.