It has become customary at times of health controversies – and there are many examples - that once the minister broaches the subject of resignations a head roll quickly follows.

And so it was with the statement on Saturday morning from Tom Costello

Less than 24 hours after Simon Harris said he would consider "personnel changes" in the governance structure of the National Children’s Hospital, the chairman of its development board announced he was stepping down.

As recently as Tuesday, the minister told an Oireachtas committee that it was "appropriate to allow due process" and he would not predetermine the outcome of a report on the cost overruns he has requested from PwC.

But with political tensions rising faster than the cost of the hospital itself, it became clear that a strong political response was required. 

The Government could not have waited until that report concluded in March before addressing the significant public disquiet.

Any expectations that the resignation will – as in previous controversies – keep the controversy away from the door of the Government are likely to be short lived.

The cost of the National Children’s Hospital for the coalition won’t be just financial, but political too.

The first reason for this is that the overspend, so far to the tune of €450m compared to what was signed off on by Government in 2017, threatens to undermine a key platform that Fine Gael will fight the next election on – that of financial management and economic competence.

Secondly, the overrun will raise doubts about the viability of what was to be another part of Fine Gael’s election campaign promise – a host of capital plans under Project 2040. 

When it was launched to much fanfare this time last year, the Government insisted it was fully costed and timetabled.

Fianna Fáil dismissed it as "fanciful" and its argument was given credence this week when Micheál Martin asked in the Dáil why anyone would have confidence that the dramatic increase in construction inflation – largely being blamed for the hospital overruns -would not apply to a whole range of other projects that have been promised.

At the Public Accounts Committee on Thursday, the chairman Sean Fleming – who described the children’s hospital costs as going "off the rails" – said it raised much broader questions. 

"The Government is talking about light rail and broadband plans which are in the billions. If this is level of governance in the system for capital projects we will be back here."

At this point, the Comptroller and Auditor General – the watchdog of State spending interjected to suggest the problem is not limited to the Children’s Hospital.

"I am actually finishing a special report on capital projects in the third level sector. There are lessons," he said. 

But the biggest political problem arising from the children’s hospital relates to the projects that will be put at risk to pay for it. 

As the past week went on, TDs were taking to their feet in the Dáil and in committee rooms, asking questions about their local promised projects and what it would mean for them. 

From now until 2022, an additional €450m will have to be found to finish the children’s hospital.

The Government says €320m of this will be through additional exchequer funding and €130m from philanthropic funding.

This year, €100m will have to be found – €50m from health and €50m from other departments, and a further €100m for the year after and the year after that again.

A list was circulated to cabinet before Christmas outlining projects that could be affected to find this money - and it is spread right across the country. 

It included bigger projects like a long-awaited Cystic Fibrosis unit in Beaumont Hospital and a second cath lab in Waterford Hospital - something that was promised in exchange for independent TD John Halligan’s support for the minority government. 

It also refers to another politically sensitive project, the relocation of the National Maternity Hospital from Holles Street to the campus of St Vincent’s, as well as new theatres for the Coombe maternity hospital, extra beds for Limerick and an upgrade for the emergency department in Galway. 

It also contains a scatter of smaller projects including the refurbishment of 90 community nursing home units in Donegal, Cavan, Louth, Carlow, Kerry, Limerick and Tipperary; Primary care centres in Clondalkin, Sligo and Monaghan town; residential accommodation for people with disabilities and mental health developments in Tuam and Naas.

No part of the country is left out. 

The Government has been consistent that no project will be cut, that they will just be delayed, postponed or "rescheduled." 

But there are considerable anxieties that have to be addressed. 

Department of Health officials said last week a clearer indication would be provided in April. 

That is a long time for question marks to lie over projects.

The growing controversy over the overspend has brought its first resignation but the opposition, as well as the chairs of both the Health Committee and the Public Accounts Committee, say this does not amount to the sort of accountability they are looking for. 

They are keeping the focus on the minister and the wider Government, and have many more questions they want answered. 

For now, Sinn Féin does not have any plans to table a no-confidence motion and Fianna Fáil said that it will not withdraw its support for the Government while Brexit negotiations are so sensitive. 

There is no immediate threat, but the Children's Hospital will be costly in both financial and political capital.