It's really lovely! I wish I could give you some idea what it might be. I think you should repost this over on the Antique Rose forum. There are more people over there that might know what it is.

I wondered if it might be Super Bonica, but that still doesn't seem to grow nearly as big as your rose. Try the regular 'Roses' Forum here; they get much more traffic, and they should be able to ID it for you, if anyone can. It's a gorgeous rose - I'd love to know what it is too!

Sorry but nobody is going to be able to reliably name a specific double pink rose cultivar using only a picture of one cut flower, without any pertinent background information. But do try the Garden Web rose identification forum - being sure to note the directions in the FAQ section of that forum about what to post for best possible results. Also which cultivar it is won't really have that much to do with how to correct the yellowing. If the lowest leaves are yellowing entirely and starting to drop off most of the time with plants in general that will be a watering issue - either too much or not enough. Again more background about the situation - and more pictures - are needed.

Hi everyone, Thank you for your quick responses and kind assistance! I apologize for the fuzzy photos; I wish I had had the time to take more. Those of us in the States all flew down to Montreal rather suddenly with the news, and all took turns keeping a 24/hr vigil over our beloved matriarch at the hospital, and then at her home when she was discharged for palliative care. That said, I am thrilled that F.J Grootendorst has been identified--thank you @Magda (Ontario, USDA4/5) @Mischievous Magpie (CO 5b) @User @stillanntn6b! Ann, thank you for letting me know about Claire Laberge--I will find her contact info! @bart bart Eilleen, not impertinent at all--this would be a perfect solution, and would love to be able to do so! I forgot to mention in my post that I now live in Kansas, and would be unable to bring cuttings across the border. Other family members are not interested/do not have the space for these roses in their garden. @Alana8aSC thank you for your kind words, I hope so too! As for rose #1, @Mischievous Magpie (CO 5b) yes, buds are mossy, and @stillanntn6b yes, they certainly did look like acorns. Another interesting feature of rose #1 is that it bloomed beautifully in part shade, if not full shade, in some spots. It is intertwined with a number of grapevines and invasive shrubs. I don't know if this feature is due to the extent to which it has been established in the area, the prized soil on the island (my husband remarked that he could see "the silica sparkling in the soil"), or the variety itself. As for rose #3, I would say that the roses were already in full bloom by the time I arrived (June 3). I will see if I have other photos. Thank you again!