The little girl was suffering from seizures and hallucinations after coming off a prescription anti-psychotic medication.
VIDEO: Marijuana gives hope to parents of brain-damaged baby
Osborne said little Madyson responded to a treatment which included a smoothie made with marijuana butter, KBOI-TV reports.
Now she has lost custody of her two children after CPS placed them with her ex-husband.
VIDEO: Parents find better life for daughter using drug made with marijuana
Osborne can only have supervised visitation with the children, a fact she says is heartbreaking.
"It tore me apart," Osborne said. "I didn't ever think that it would come down to this but it did."
VIDEO: Dad fights for access to marijuana for epileptic son
The mother is facing a misdemeanor count of injury to a child, a charge she says she is going to fight.
"I'm not going to stop. I won't stop," Osborne said. "If it takes me two years, then it's going to take me two years."
Osborne has another fight on her hands, as well. She was seen rallying in front of the Department of Health and Welfare, calling for medicinal marijuana reform.
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The department says for now, the law is the law, and that marijuana is illegal. Their main concern, they say, is for the safety of children.
In Idaho, medicinal marijuana is only legal for a small group of children suffering from epilepsy for now.
Those enrolled have to go through several tests before they are approved for such treatment.
Osborne's children, they say, was not on such a list.
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