How many families or other relationships does this describe? The embers of resentment suddenly fanned into flame by a passing question or comment? Pernicious and pointless. I believe it was Mandela who said that resentment is like swallowing poison and hoping it will kill your enemy.
‘His son’s question had fallen like a bit of dry fuel on the embers of a long unextinguished resentment.’
Source: George Eliot, Adam Bede (Harmondsworth: Penguin, 1985 (1859)), p. 383
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