This poem is written in the Sonnet style but is not a Sonnet per se.
Three quatrains, rhyme scheme ABAB, CDCD, EFEF, in iambic pentameter, with a volta around line eight and a concluding couplet, GG, is certainly Sonnet form but the subject matter is not quite Sonnet material.
DOGS
He’s a determined one and no mistake.
While others of his age group fade away,
he adds a candle to his birthday cake
and seems immune to ageing and decay.
He is a character, one must admit:
an old man who seems younger than his son,
a giant with a coruscating wit,
a raconteur, if ever there was one.
Yet there are times, behind his ready smile,
one glimpses some deep darkness firmly chained,
like two fierce dogs, both straining all the while
to be let loose, their fury unexplained.
He buys another round. We all drink deep.
For now those two grim dogs remain asleep.
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