Is there a person/time/way to go about getting your grandmothers engagement ring for the purposes of getting engaged?

I was talking with a buddy of mine who is pondering/planning to marry his beau. He thought it would be romantic to get ahold of his grandmother’s engagement ring. He was close to her as a child, but not as much as he grew up (though save for his 8 year old and younger cousins, he and his brother were the only grandchildren she regularly saw).

But how does one even go about doing that? His grandmother is sadly reaching a point where she’s not all there cognitively. He could ask her, but there would definitely be a feeling of taking advantage of her (or concern that she may not even understand the question). His oldest uncle is basically her care taker, he could ask him or his own father… but the questions continue. Do you wait until after your grandmother has passed to ask the family “elders” about using the ring (and if so, how do you bring up such a sensitive topic around the time of her passing, since you would want to chime in before she ended up buried with it)? If asking before her passing do you ask to use the ring prior to her death or after her death (the grandfather has been dead for over 15 years if that has any bearing)? The ring’s style is dated, and he would likely want to make changes to it (most particularly a new band, or some kind of plating on the existing one), would that be faux-pas or not allowed? How would you mention that part?

The only male grandson other than my friend who would have an argument to have the ring for the same reason, is my friends older brother, who has already been married and divorced. The other grandchildren in the appropriate age range are already married, and/or women. There are several very young grandchildren, but none of them will really even be at a “marrying-age” for at least another 5–6 years (the eldest is like 13). But in general how do you avoid family drama from this situation/question?

He tells me engagement would be at least a year off, so he has some benefit of time (assuming his grandmothers health holds out). But he was concerned enough to ask me to ask, lol.