Tom Parsons is Winston's neighber in 1984. He lives with his wife and children, whom Winston is familiar with when he visits their home to hlep with common tasks. Like Winston, Parsons is a member of the Outer Party and works near Winston in the Ministry of Truth.
Both men, as most citizens, live in fear of Big Brother and vaporization. Similarly, both men work in sensitive areas: Winston works in erasing all history of vaporized individuals while Parsons is working to create a new version of the dictionary which pares down the human language, and ultimately thought. Therefore, both are privvy to information that could expose Big Brother as a fraud.
Ultimately, both men are caught for their crimes. Winston is confined and rehabilitated while Parsons is vaporized.