28 D appears in Chambers under the entry for the definition in the clue, though not on its own. The preamble says 'Chambers... is the primary reference' - I don't know if that's enough to cover this?
I agree with others that this was a most enjoyable puzzle and I really appreciated the straight-forward instructions. Thank you Hedge-sparrow. I once brought up two young protagonists who had lost their mother, and they were quite enchanting.