Please understand that no attorney can guarantee you what is "enough" to get custody changed. However, we can provide some guidance as to what might be sufficient. As to that...
I would suggest that you have enough here to warrant a change in the custodial arrangement. As you may know, a change in the custodial arrangement is typically based on a substantial change in circumstances. Here you have some serious issues with the mother. The mother has failed or refused to facilitate the child's therapy. The mother has demonstrated that she is unable or unwilling to help the child with school. Perhaps most disturbing, there is evidence that she is using illegal drugs.
I would suggest that this evidence is sufficient to get a judge to change the custodial arrangement.
Please let me know if anything requires clarification.
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