The Pillars Team

Derek Carvalho, LMHC, is a dedicated mental health therapist with extensive experience providing compassionate care to diverse populations experiencing a wide range of mental health and substance use concerns. With a strong background in cognitive behavioral therapy (CBT) and dialectical behavior therapy (DBT), Derek specializes in helping clients develop effective coping strategies and build resilience.

Prior to joining Pillars Health Group, Derek worked in substance use and mental health treatment settings, where he honed his skills in addressing the unique challenges associated with addiction and recovery.

With years of experience in the mental health and substance use treatment field, Lauren Rondeau, LCSW, is deeply committed to helping individuals navigate their healing and recovery journeys with compassion, empathy, and evidence-based care. She is passionate about supporting clients through life’s challenges while empowering them to build resilience, develop healthy coping skills, and achieve lasting wellness.

Throughout her career, Lauren has worked with diverse populations across a variety of clinical settings, providing individualized support for those struggling with mental health concerns, addiction, trauma, and co-occurring disorders. Her approach is rooted in creating a safe, supportive, and nonjudgmental environment where clients feel heard, valued, and encouraged to grow.

Outside of her professional role, Lauren cherishes spending quality time with her son and values the importance of family, balance, and connection. Her personal and professional experiences continue to inspire her dedication to helping others find hope, healing, and recovery.

McKenzie Tessier, MS, is a master's-level clinician who is passionate about supporting individuals experiencing challenges related to mental health, emotional regulation, and substance use. She is committed to creating a supportive, nonjudgmental environment where clients feel comfortable exploring their thoughts, emotions, and experiences while working toward meaningful, lasting change.

McKenzie enjoys helping clients develop practical coping skills, improve emotional awareness, and build healthier patterns of thinking and behavior. She has a strong interest in behavior therapy and incorporates Dialectical Behavior Therapy (DBT) skills into her work, helping clients strengthen emotional regulation, distress tolerance, and interpersonal effectiveness.

Prior to joining Keys Behavioral Health, McKenzie worked in medication-assisted treatment (MAT) settings and with adolescents experiencing behavioral disorders. These experiences provided valuable insight into the complexities of addiction, behavioral health challenges, and the importance of individualized, person-centered care. She is dedicated to helping clients build confidence, develop effective coping strategies, and work toward personal growth and overall well-being.

With a deep commitment to helping others find healing and stability, Dawn brings compassion, empathy, and authenticity to her work in the mental health and recovery field. Her dedication is rooted not only in professional experience, but also in lived experience navigating mental health challenges, trauma, and addiction.

This perspective allows her to connect with individuals genuinely and meaningfully, meeting people where they are and approaching each person with understanding. Dawn believes that reaching out for help can be one of the most difficult decisions a person makes, so she strives to create a safe, supportive environment where individuals feel heard, respected, and encouraged to begin their journey toward wellness.

Brianna Perrino is a master's-level clinician who has worked with children, adolescents, and adults from diverse backgrounds, helping them overcome personal struggles and develop healthier, more fulfilling ways of thinking and living. She incorporates a variety of evidence-based therapeutic approaches, including cognitive behavioral therapy (CBT), dialectical behavior therapy (DBT), motivational interviewing (MI), and solution-focused therapy (SFT).

Brianna has extensive experience providing mental health treatment in outpatient, in-home family therapy, and partial hospitalization settings. Throughout her career, she has worked with clients facing severe mental health challenges, including mood and anxiety disorders, as well as suicidal ideation.

She is committed to helping clients stabilize their emotional and mental health while developing practical coping strategies and skills that support long-term healing and well-being.

Bella Nugent is a clinician specializing in mental health and co-occurring substance use treatment at the PHP and IOP levels of care. She has experience facilitating both individual and group therapy using cognitive behavioral therapy (CBT), dialectical behavior therapy (DBT), psychoeducation, process-oriented therapy, and experiential interventions. In addition to her clinical work, Bella has supported program development and coordination within intensive outpatient settings.

Bella is especially passionate about working with individuals navigating trauma, complex trauma, and post-traumatic stress disorder (PTSD). She strives to create a therapeutic environment that feels emotionally safe, authentic, and grounded in genuine human connection.

Her approach balances insight-oriented exploration with practical coping skills, helping clients build emotional regulation, resilience, self-worth, and self-compassion. Known for her warm, collaborative, and approachable style, Bella often incorporates humor and authenticity to help clients feel comfortable engaging in meaningful therapeutic work and creating lasting change.

Abigail McMillan brings a multidimensional clinical background to Pillars Health Group in Tewksbury, with a focus on supporting individuals through mental health challenges, substance use recovery, and significant life transitions. Her approach is highly individualized, drawing from a variety of therapeutic modalities to ensure care is tailored to each client's unique needs and circumstances.

Prior to joining Pillars Health Group, Abigail gained experience in PHP and IOP programs, correctional facilities, and clinical research. This diverse background has provided her with a broad clinical perspective in treating mental health conditions, substance use disorders, dual diagnosis, and trauma-related challenges.

As she completes her advanced clinical credentials in Clinical Mental Health Counseling, Abigail is dedicated to helping clients develop practical skills, strengthen resilience, and achieve lasting therapeutic success.

Sasha is a Certified Peer Specialist and Wellness Recovery Action Plan (WRAP) facilitator who brings both professional training and lived experience to her work. Having personally navigated mental health challenges and trauma, she offers a compassionate, understanding presence grounded in resilience and real-world insight.

She believes that asking for help is one of the strongest and most courageous things a person can do. Sasha is dedicated to creating a safe, supportive space where individuals feel heard, respected, and empowered to open up at their own pace. She is passionate about advocacy and helping others move toward healing and self-discovery while emphasizing the powerful connection between physical activity and mental well-being.

Outside of work, Sasha enjoys writing, art, and music—creative outlets that continue to support her own wellness journey and inspire the care she provides to others.

Link Erickson is a dedicated Case Manager at Pillars Tewksbury with a strong commitment to helping individuals navigate the challenges of substance use and mental health recovery. A proud United States Marine Corps veteran, Link brings discipline, integrity, and compassion to his work every day.

Drawing from his own long-term recovery from alcoholism and extensive experience working a thorough Twelve Step program, he understands firsthand the courage and perseverance required to build a new way of life. His personal journey allows him to offer hope, understanding, and practical guidance while fostering trusting, supportive relationships with every client he serves.

Link is passionate about empowering others to achieve lasting recovery by meeting them where they are and helping them overcome barriers. Whether coordinating services, advocating for clients, or providing encouragement, he is committed to helping each person build a strong foundation for long-term recovery and a more meaningful life.