Don't despair. There have always been people with fringe ideas. That doesn't mean that others agree, nor that even she will feel the same in a few years. Several of my friends have become grandparents in the last decade or so, and from what I can tell all those involved are enjoying the experience immensely.
In my case at least, the grandparent era has brought much joy.
For my wife and myself, the main thing (other than the love/sentimental part) that it did was to open us both up to the idea of long car trips. I figured that financially, it broke more or less even to ferry and drive between Mallorca and the Spanish mainland, enjoy a relaxed trip through France, take the ferry across the Channel to England, suffer the rather hellish drive up north to Scotland, spend six weeks there between the two parental homes, and drive home again, when compared with flying and hiring wheels for six weeks. I loved those personal versions of a European “Route 66”… we enjoyed them for several unforgettable years; sadly, my first heart attack put an end to that, when my wife refused to take the chances that I might have a second, which I did.
After she died, it crossed my mind to say the hell with it, and just drive there again, but both sets of parents had, by then, passed on, and even if I had elected to simply tour France again, a broken heart wasn’t gonna be the best travelling companion: in other words, a waste of both time and ever-shrinking resources.
If there’s a moral to it, never put off what you can do today, because come mañana, maybe you won't be able to do it at all. In other words, if you desire - and have the bread - buy yourself those two friggin’ models of the Q!