Keira Christina Knightley amụrụ na 26 Machị 1985, na Teddington, London, nye ndị na-eme ihe nkiri Sharman Macdonald na Will Knightley. Nne ya bụ nke Scottish na Welsh, ebe nna ya bụ Bekee. E bu n'uche ka a kpọọ ya "Kiera", ụdị Anglicized nke "Kira", aha nke onye Russia ice skater, Ivanova, onye nna ya nwere mmasị na ya. Agbanyeghị, Macdonald mehiere aha mgbe ọ gara ịdebanye aha nwa ya nwanyị, na-ede "e" tupu "i". Knightley nwere nwanne nwoke nke okenye, Caleb. Macdonald rụkwara ọrụ dị ka onye na-eme ihe nkiri mgbe ọrụ ya dị ka onye na-eme ihe nkiri gwụsịrị. Ọ kpọbatara ụmụ ya na ballet na ballet n'oge ọ dị obere. Nke a mere ka mmasị Knightley na-eme ihe nkiri, ọ lekwasịrị anya na onye nnọchi anya na-eme ihe nkiri n'oge niile ọ dị afọ atọ.
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