Gallifrey Under-Tens Swimathon
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The Thirteenth Doctor claimed to have once been thirteenth "in [their] line" in the Gallifrey Under-Tens Swimathon, a swimming competition.
She used this to introduce herself facetiously to Space Lord Draal, First Admiral of the Fleet, fourth of his line, whom she regarded as a tyrant. (PROSE: The Secret in Vault 13 [+]Loading...["The Secret in Vault 13 (novel)"])