Andrew Landeryou made the comments in his eulogy to Ms Kitching, who was farewelled by politicians from across the party divide at Melbourne's St Patrick's Cathedral on Monday.

But former Labor leader Bill Shorten has called on Labor to unite in the wake of Ms Kitching's death, saying his close friend and political ally would want her colleagues to "channel their grief" toward winning the upcoming federal election.

The aftermath of Ms Kitching's shock death from a suspected heart attack has been marred by allegations she was was bullied and frozen out by senior Labor colleagues and her political future put at risk amid a messy preselection.

The claims, which have been pushed by Ms Kitching's closest friends and allies, have put the spotlight on Anthony Albanese and the culture within the Labor movement just weeks out from the federal election campaign.

Mr Landeryou used his eulogy to call out the "unpleasantness of a cantankerous cabal" of Labor figures - not all of whom were in the Federal Parliament - which was targeted at his late wife.

"I hope it's sufficient to say that she deserved so very much better," Mr Landeryou said.

In his eulogy, Mr Shorten signalled Ms Kitching would want the Labor family to come together and harness their emotions toward defeating Scott Morrison at the looming federal election.

"This is not a political speech and with the greatest respect to her true friends across the political aisle ... I believe Kimberley would want everyone in her Labor family to channel their grief, gather their strength and move onwards from here together in the pursuit of that goal [winning the election]," he said.

"The Kimberley that I knew and honour would say now there is a time for coming together and a time to heal."

Mr Albanese has faced growing calls to investigate allegations that Ms Kitching was bullied and ostracised by senior Labor figures, including Penny Wong, Kristina Keneally and Katy Gallagher, before she died.

The trio rejected the claims as "untrue" in a joint statement published after a week of media reports about the alleged treatment of Ms Kitching.

The three opposition frontbenchers reportedly attended the funeral.

Prime Minister Scott Morrison, who wasn't among the large number of Coalition members who attended Ms Kitching's funeral, has continued to attack Labor's response to the allegations.

"The Labor Party and Anthony Albanese in particular has been very quick to throw stones, very quick to make accusations, but when he has to [deal] with the same issues in his own house, well, he shuts up shop and gets into the basement," he told 4BC radio on Monday morning.

Ms Kitching had yet to be preselected on Labor's Victorian Senate ticket for the upcoming federal election, casting a cloud over her political future.

Allies of the former lawyer and union official blamed factional game-playing for the stress the 52-year-old was under before her shock death. She was also battling a thyroid condition.

After entering Federal Parliament in 2016, Ms Kitching forged a reputation as a foreign policy hawk and a defender of human rights and democracy.

She was recently honoured for her work pushing for the introduction of Magnitsky-style laws in Australia, which are now being used to sanction Russian President Vladimir Putin for waging war on Ukraine.

In a statement read on behalf of Senate president Slade Brockman at Monday's funeral service, Labor powerbroker Don Farrell said Ms Kitching had a "clear moral compass which she always held true".

"She knew what we have here in this country is something worthy of praise, and worthy of defending," Senator Farrell said.

"A democrat, an optimist, a realist, a believer ... the Senate will be poorer without her."

In his eulogy, Mr Shorten said Ms Kitching's death had left a "great hole".

"A black hole, almost, with its own gravity, the kind caused by the collapse of a massive star," he said.

A number of government members, including ACT Senator Zed Seselja, Deputy Prime Minister Barnaby Joyce and Finance Minister Simon Birmingham, were spotted entering St Patrick's Cathedral ahead of the start of the funeral at 2.30pm.