Alex Williamson, the daughter of disgraced former Health Services Union chief Michael Williamson, has left her role as a media adviser in Prime Minister Julia Gillard’s office.

Gillard communications director John McTernan confirmed this afternoon that Williamson’s last day was today but said it had nothing to do with her dad’s questionable union activities.

“She’s leaving under her own steam … I’ve been reorganising my office to get it into shape for the general election. She goes with our blessing and best wishes for the future. It’s a time a year out from an election when people choose to stick or move.”

McTernan said Williamson would now “decompress for a bit” — a common move for departing PMO staffers crushed by relentless 16-hour days.

Details have emerged of a renegade Facebook post in which Williamson is alleged to have criticised “the media” for hounding her family over the HSU saga. But McTernan said that was unrelated to Williamson’s decision.

When the full Temby report into the HSUEast branch was released this week, Michael Williamson’s wife Julieanne’s company Canme Services was revealed to have received $400,000 in payments from the union over four years between 2005 and 2009. The “a” in Canme stands for Alex.

Alex Williamson once shared a house in Canberra with former NSW general secretary turned senator Mark Arbib. She has been working in the PMO for 5 years.

“This is probably the best move for all concerned,” one senior ALP source said this afternoon.