AMs will meet in private later to mark one year since the death of former Labour minister Carl Sargeant.
Mr Sargeant was sacked by First Minister Carwyn Jones last year after sexual harassment allegations.
The Alyn and Deeside AM was found dead at home days later, with hanging given as his provisional cause of death.
Labour group chairwoman Vikki Howells said: “We all miss Carl tremendously, he was a friend to us all and a fantastic colleague.”
His death led to a series of investigations, with an independent probe into how Mr Jones handled the sacking yet to begin.
Mr Sargeant’s son Jack succeeded his father as an AM after winning the Alyn and Deeside by-election that followed his death.
Welsh Conservative assembly group leader Paul Davies said: “Carl was a huge personality in the assembly and made a significant contribution in Welsh politics, so his passing – a year on – is still difficult.
“The Sargeant family, the assembly, and the people of Wales are still waiting for answers surrounding his death and I hope that they come to light in a fair, legal, and transparent manner.”
A tragedy that shocked Wales’ political class
By Felicity Evans, BBC Wales political editor
The death of Carl Sargeant left his family grief-stricken and the Welsh Government and Labour party in crisis.
Within six months Carwyn Jones had announced plans to stand down as first minister; his authority sapped away by a cycle of claim and counter-claim about his handling of Mr Sargeant’s sacking.
Those competing to replace him have all spoken of the need to heal the wounds within the Labour group of AMs and draw a line under a tragedy that shocked Wales’ political class to the core.
But that will be difficult, with the independent inquiry pending and with Mr Jones due to give evidence at the inquest into Mr Sargeant’s death.
And what of the wider questions that go beyond this tragedy? How do you treat allegations in a way that is fair to both the accused and accuser?
And how can institutions create a culture and a complaints system that has the confidence of those they are supposed to protect?
Plaid Cymru leader Adam Price said the anniversary was a “sad and poignant occasion for all of us” that will be “focusing a lot of our minds on the terrible loss and trauma that his family would have gone through”.
“It’s been a dark and difficult chapter in Welsh politics,” he said.
The independent investigation, commissioned by the first minister, was suspended before it began following legal action from Mr Sargeant’s family.
Their appeal to a court decision to refuse a request for a judicial review will be heard in London next week.
Mr Jones ordered the independent probe, due to be led by Paul Bowen QC, following demands from Labour politicians.
An inquiry into alleged leaking of the news Mr Sargeant was going to be sacked found “no evidence of prior unauthorised sharing of information”.