You have many questions, and a complicated situation. All answers are going to end with the fact that you need to take a copy of this apparently extensive file to an attorney to thouroughly review. It appears that through a serious of events, CPS has temporary primary conservatorship of your grandchildren, Dad has posessory conservatorship, a third party (niece?) has temporary placement through CPS, and you have no rights under any the existing court order. Dad (your son?) can file to modify his rights, and it sounds that you will be necessary to establish his stability and support. An attorney can work with you develop a strategy that might enlarge your access to the children.
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