His daughter , Hilary Armstrong , was his successor .
Defeated by the Conservative incumbent in Sunderland South in the 1955 and 1959 General Elections , Armstrong was Member of Parliament ( MP ) for North West Durham from 1964 until his retirement in 1987 .
Armstrong 's daughter , Hilary Armstrong , was his successor .
Defeated by the Conservative incumbent in Sunderland South in the 1955 and 1959 General Elections , Armstrong was Member of Parliament ( MP ) for North West Durham from 1964 until his retirement in 1987 .