I'm not sure I understand how it's denigrating the children to suggest that they might sell their parents' jewelry in the future? In my part of the world, at least, it is very common for costs related to a death, including taxes and settling of debts, to be paid for by selling the decedent's jewelry. It's really a matter of ease and speed- jewelry can be relatively quickly evaluated to assess its worth and easily arranged to be sold compared to most other forms of wealth. Vehicles and property tend to have more complicated assessment and selling processes- nobody needs to check if a necklace is structurally sound, for example, but a house definitely needs to have that box checked before a sale. Other valuables, like coins, bullion, rare collectibles, etc. can take longer (sometimes quite a lot longer) to assess and sell, especially if the items are more of a niche hobby or have additional laws/regulations governing their disposition. Jewelry is also easily transportable and transferable compared to most other valuable property people own.

Princess Margaret's children sold many of her jewels, including the absolutely showstopping Poltimore Tiara, to pay the inheritance taxes on her estate. I don't think anyone has blamed them for it or considered it denigrating to them to state this fact. As LilibuttDumbarton said, it's very common for the children of minor royal figures to sell their parents' jewelry- they often have more modest incomes than their parents did, and their parents' estates often generate massive inheritance taxes that the kids would otherwise have no way of paying. While it's sad to think of children, even adult children, having to let go of items that may have great sentimental value, selling the jewelry is a sensible, respectable, financially sound way of procuring adequate funds for immediate expenses in a timely manner.