WHEN Mary Lou McDonald and Michelle O'Neill became Sinn Féin's new leadership team little over 21 months ago, few would have a predicted a challenge to their authority so soon.
That the challenge has come from John O'Dowd, one of the party's most able and articulate representatives in the north, is equally surprising.
Yet Ms McDonald speaks of the Upper Bann MLA's virtually unprecedented gesture of public dissent as if it's an everyday occurrence.
She insists she's entirely relaxed about the vote at this weekend's ard fheis in Derry and fully supports the former Stormont education minister "in his prerogative".
But Sinn Féin is different from other political parties and whereas a challenge to the deputy leadership of the SDLP or Ulster Unionists would be a very public contest, debate around this issue has been closed down, taking place if at all behind closed doors.
"The ard chomhairle had a discussion and took a decision around how the contest might be held, bearing in mind it’s an internal position, bearing in mind that the electorate is the party membership and the party delegates," Ms McDonald says of the process, which hasn't included any hustings events where candidates get to set out their aims and vision for the party.
She points out that both Ms O'Neill and Mr O'Dowd are members of Sinn Féin's ruling executive, so had a hand in deciding the "best, most orderly and fair way" for the contest to take place.
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The Sinn Féin president rejects suggestions that this arrangement is bad for the party's image and that it hinders the challenger's prospects of success, describing it as an "absolutely level playing pitch".
"They (the two deputy leadership contenders) have been talking to people right across the country, right across the 32 counties," she says.
"There’s nothing or nobody stopping or impeding those conversations at all."
Ms McDonald also insists that if defeated, John O'Dowd will remain a key member of the party: "I am absolutely confident that John as a person of significant standing and considerable talent will always feature as part of the Sinn Féin leadership."
When those talents can be potentially put to use in a Stormont executive is not known but the Dublin TD says it's "intolerable" that the devolved institutions have been dormant for more than 1,000 days.
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She is clear where she believes the blame lies and what would break the impasse.
"The truth is, if there were the political will to embrace power-sharing on the part of the DUP, I believe we could land at an agreement actually quite quickly," she says.
"The difficulty is they have been distracted and bedazzled by Westminster and that didn’t end well for them as we all saw and predicted."
Ms McDonald would like to see talks reconvened "as soon as a window opens", acknowledging that an election campaign "doesn't provide an ideal backdrop" for negotiations.
"The ball is at the feet of the DUP and the British government, whoever that may be at the end of this election."
As an Irish republican, the Sinn Féin leader says she is unable to welcome Westminster's recent imposition of legislation liberalising abortion law and legalising same-sex marriage.
"But I have to say that I understand that people living in the north of Ireland are now happy with the fact that rights denied have become a reality," she says.
"I think this should sharpen everybody’s focus and particularly the DUP’s focus in understanding that real power-sharing is where it’s at and if they are unhappy or disgruntled with decisions that are made at the Westminster level, then I think that raises big questions for them in terms of what they have prioritised and how they have carried themselves over the last number of years."
Ms McDonald has also described as "wrong" Leo Varadkar's reported rejection of a call from civic nationalism to establish a Citizens Assembly to examine Irish unity.
The call came last week in letter signed by more than 1,000 nationalists from across Ireland and beyond, including commentator Fintan O’Toole, Boston mayor Marty Walsh, economist David McWilliams, concert promoter Peter Aiken and businessman David Gavaghan, the former head of Stormont’s Strategic Investment Board.
The Sinn Féin leader believes there should be a border poll in three-to-five years and that formulating the shape of a potential new state should begin immediately.
She described the Fine Gael leader's rejection of a forum to discuss unity as "short-sighted".
"The taoiseach is wrong to imagine he can wish this away or say he wants to talk about Irish unity but not now – that’s not how politics work, that’s not a healthy and responsible thing to do," she says.
"If he is citing concerns around political unionism then that is wrong because I know people within the unionist community, within the Protestant and loyalist community, are talking about this issue."