Complex sentence: After the birth of their first son in 1955, Hobson gave up acting and devoted herself to Profumo's career, accompanying him on many official overseas visits he made while a junior Foreign Office minister.
Split into simpler sentences: After the birth of their first son in 1955, Hobson gave up acting and devoted herself to the furtherance of Profumo's career. She accompanied him on many of the official overseas visits that he made as a junior Foreign Office minister.