There really aren't "grandparent rights." There is a very limited situation in which the parents of a deceased parent can obtain a visitation order. That doesn't seem to apply here.
Indiana's rules on this issue, along with other states, stem from a US Supreme Court decision which upheld the fundamental interest a parent has in parenting their children.
Only if the mother and father were unfit would you have a cause of action in which you could attempt to obtain a guardianship. But proving unfitness is very difficult. You would have to consult with an attorney to determine whether the family's living conditions are bad enough to meet this burden.
Avoid the temptation to involve child services. Only call DCS if you believe your grandchild is immediate danger of serious harm.
This answer is for informational purposes only, and it not intended to create an attorney-client relationship. I've had only the limited amount of information provided in the question from which to form an answer. Your best course of action is to set up a formal consultation with a qualified attorney in your area.
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