Dear Old Toad,
That is EXACTLY what I needed to do! Thank you, so very much! For some reason when I connected my iPhone it dumped a whole bunch of photos into one single "event" (but not all of them, just to confuse me) over a long time from (most of November, in this instance). It also happened to have chosen the most innocuous photo of the bunch to make the "key photo" so that I wouldn't even think of looking in it for the ones I was missing. So now I've gone through and separated out the events and then joining them to the already existing events of the same event in the library! LOL!
Any idea what I may have done wrong to do this? Perhaps I need to connect directly with my Mac on a more regular basis (with photostream I get lulled into not connecting very often).
Also, would you know what is the difference between "create event" and "split event?" At first blush they seem to do the same thing, but I'm just not sure.
In any case, THANK YOU for solving my problem!