Two Fianna Fáil deputies are today putting a motion to the party, opposing plans to build the new National Children's Hospital at St James in Dublin.
The move by James Lawless and Jack Chambers follows a briefing for TDs and Senators last week, which challenged claims that the inner city hospital is the best site for the new facility.
Jonathan Irwin, the Founder of the Jack & Jill Children's Foundation says it is about time for the Government to wake up and listen; instead of "sleep-walking into a catastrophe".
Mr Irwin said: "This has always been a disaster, it's never been about children, it's always benn about adult balances - it's academic, medical, political, never about children.
"And now of course as we've seen Tony O'Brien said at a billion and two this is getting out of hand, it's ridiculous, and I think the tide is changing."
Mr Irwin said a briefing for TDs and Senators last week has begun to change peoples' minds about where the new hospital should go.
He said: "The reality of the situation is the fat lady hasn't sung. Last week, thanks to Mattie McGrath the independent from Tipperary, we had the chance to make a presentation in Leinster House - the Connolly Hospital for Sick Children and myself.
"And my God I couldn't believe it, nearly 60 TDs and senators were there and nobody spoke in favour of St James'."