flˈɛtʃɚ wʌz bˈɔːɹn ɪn ɐ stɹˈiːθæm nˈɜːsɪŋ hˈoʊm ɪn nˈaɪntiːnhˈʌndɹɪd twˈɛnti, ðɪ ˈoʊnli tʃˈaɪld ʌv dʒˈɑːn ˈɑːɹtʃɪbˌɔːld flˈɛtʃɚ wˈʌn θˈaʊzənd ˈeɪthˈʌndɹɪd ˈeɪɾi sˈɛvən?mˈaɪnəs nˈaɪntiːnhˈʌndɹɪd sˈɪksti ˈeɪt, ɐ fˈɑːɹmɚ ænd ɹᵻtˈaɪɚd ˈɑːɹmi mˈeɪdʒɚ, ænd kˈæθɹɪn mˈɑːɹɡɹət ɹˈɪtʃɚdsən wˈʌn θˈaʊzənd ˈeɪthˈʌndɹɪd ˈeɪɾi ˈeɪt dˈæʃ nˈaɪntiːnhˈʌndɹɪd sˈɛvənti nˈaɪn.
Fletcher was born in a Streatham nursing home in 1920, the only child of John Archibald Fletcher (1887?-1968), a farmer and retired army major, and Katherine Margaret Richardson (1888-1979).