Applying for access to neices.

Courts would be unlikely to intervene

I think its a long shot either way. But if the question of guardianship, custody, etc of children is already before the court, and the court has a paramount duty to act in the best interests of the children, then there might be some way in which you could shoehorn in an application in the context of those proceedings, or get one of the parents to raise it as an issue — be worth exploring, anyway. But if there's no family breakdown, if it's simply a case that the parents do not facilitate, or actively prevent, the children having a relationship with their uncle or aunt, it's very hard to see the court intervening, or even any basis on which the uncle/aunt could bring an application.

If uncle/aunt thinks the situation threatens harm to the children they can take the matter up with Tusla, and depending on the facts Tusla might launch proceedings in which the children's relationship with uncle/aunt is raised as an issue but, frankly, it would be a fairly minor issue in the overall proceedings. And it would require extraordinary facts that the OP doesn't even hint at.

Long story short: "I don't get to see my nephews/nieces" is not, on its own, grounds for a court application. Nobody has a legal right to see someone else's children.

This is very very unlikely to achieve anything. I would strongly suggest contacting a solicitor versed in family law.

As someone who is in a blended family and experienced several court cases. The courts are set up to look after the child number 1, and the parents number 2, and no one else. The way it should be.

A relative (other than a parent, obviously) have no guardianship rights unless (a) the parents have died and have by their will appointed the relative to be guardian, or (b) a court has made an order appointing the relative as guardian.

Threatened by who?

Well to the Lionel Hutzes of this world it matters little what the law actually says provided they can quote it at people to frighten them.

I'm not sure if you've acquainted yourself with the facts of this case, you're quoting legal theory and most of what you're saying does not apply in this case.

One of the child's parents is deceased and 'There are no concerns whatsoever with surviving parents skills or welfare.' No third party was appointed as guardian so the surviving parent is the child's sole guardian.

The OP's concern is not about the child's welfare under the surviving parent, he or she is concerned about allowing an unsuitable cohort of relatives access to the child - 'The aunts uncles are not the type of people youd want your children around'

I was looking at the original not the revised version.

I really should have copped it though, given there is no section 11B in the original.

Ignore. Until you get a court summons, let them send all the solicitors letters they want.