What is Dialectic Behavior Therapy?
DBT is the most effective form of psychotherapy for treating a condition called Borderline Personality Disorder (among other conditions). Ideally, it involves both weekly individual therapy as well as a weekly didactic (group teaching type format) component. “Homework” is also a significant portion of the treatment (practicing in real life the skills they learn in group). In the USA, this most frequently takes place around twice weekly (once a week individual therapy, once a week didactic group). It may be possible that your brother’s therapist is choosing a more intense treatment format (e.g., intensive outpatient). I am unfamiliar with “counselors garden”. Nothing you have described above is unethical. Hope this is helpful, ~Dr. B.~ p.s. If by “doing the counselor’s garden” you mean that your brother is EMPLOYED/working for the counselor (doing his/her landscaping, for example) then yes, that is unethical in most situations.