First and foremost, I am so so sorry for your loss. An unimaginable tragedy only to be followed by another tragedy of having siblings separated for so long. There are indeed laws that support what you are looking for. The cases become complicated, though, so you should sit down with a family law attorney to strategize the best way to move forward. Good luck to you and your children.
You'll need to file a motion to seek visitation with the children. Unfortunately, the natural father has a paramount right to custody. However, you have a right to parenting time and visitation with the children if you can show that it is a haunted them if you are removed from their lives.
I am so sorry for your loss and I think it is so impressive that you wish to honor your wife's wishes. My advise is to file a motion for parenting time, based on your having been a psychological parent, and the best interest in the children keeping in touch with siblings. I sure hope you win this.
Please be advised my answers to questions does not constitute legal advise and you should not rely on it, due to the fact that we have never met, I have not been aprised of the facts in you case nor have I reviewed any documents.
You realy don't have many rights because of the way the laws are structured.
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