Either you or the parents can petition the court to determine parenting time that the parents will get with the great niece. Although grandparents can petition for grandparent visitation, it has been severely limited by the US Supreme Court in recent decisions. So, I would simply tell them to petition the El Paso County District Court for parenting time and you will comply with any orders from the Court. You can also petition the Court for the parents to pay child support to you as the child's guardian.
The information provided in this answer does not create an attorney-client relationship and is not considered to be legal advice.
You can ask for allocation of parental responsibilities and have the court establish a parenting plan which will be the rules for contact with the parents. You can also seek child support. It would be best to work with an attorney as this is a complex undertaking. Good luck to you.
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