If there are no current orders in place, you are within your right to take the child into your care, and the grandmother has no legal avenue to stop you as she has no parental responsibility for the child.
I don't ordinarily raise this as a point because I am a firm advocate for amicable outcomes, rather than ones that risk conflict, but if you were the primary carer for the child for eight months during her infancy, and she is now only 11 months old, then it's very likely that her primary emotional attachment is to you, not the mother. If you are now only seeing her for one hour, supervised, each week, then I would argue the child's best interests are not being met because she has been unilaterally separated from what may potentially be her primary attachment figure.
So, with the above considered, please know that this is a federal matter, and the state police have no powers to intervene if you were to remove the child from the grandmother's property without her consent. You don't need her consent - she doesn't have parental responsibility for the child, which means she has no say in care arrangements whatsoever. While ever there are no orders in place, you have as much power as the mother to have the child live with you and stipulate supervised time to the grandmother.
Fathers tend to be backbenched and forced into believing they're the 'secondary, less-important parent' because they didn't carry the child in their womb, but this is not the case at all. The court recognises the benefit to children of having a meaningful relationship with both of the child's parents as a primary consideration in what meets their best interests.
Just a thought.