Understanding Phelan-McDermid Syndrome: Benji and Giulietta’s Journey

Phelan-McDermid Syndrome (PMS), also known as 22q13 deletion syndrome, is a rare genetic condition caused by the loss or dysfunction of the SHANK3 gene, along with other genes essential for building neural networks. SHANK3 plays a vital role in brain development, and its absence is one of the known genetic causes of autism spectrum disorder (ASD).

Phelan-McDermid Syndrome , often called PMS, looks different in every individual. Benji and Giulietta share the same diagnosis, but the way it shows up in their daily lives is uniquely their own. Their experiences are a good reminder that with PMS, challenges are rarely isolated.

Everything tends to be connected.

Low muscle tone, sensory processing differences, and proprioceptive challenges all interact with one another. Together, they shape how a person learns, communicates, and moves through the world.

Sensory processing plays a big role in their day to day lives. This is the brain’s way of taking in information from the environment and making sense of it. For individuals with PMS, that process can be inconsistent or slower to organize. Benji and Giulietta both have an under-responsive sensory profile. It often takes them longer to notice or react to sounds, touch, or movement. At times they may seem disengaged, but in reality their brains are working hard to interpret what’s happening around them.

Physical development comes with its own set of challenges. Low muscle tone is a core feature of PMS, and it affects everything from large movements like walking and climbing to smaller tasks like holding objects. Movements can take more effort, and fatigue can set in quickly. This often overlaps with Dyspraxia, which affects motor planning and coordination. Even simple actions can require extra thought and repetition.

That said, progress is always possible. With time, practice, and the right kind of support, both Benji and Giulietta have continued to build strength and confidence in their own ways.

One of the most helpful approaches for them has been building movement into everyday routines. A body-based approach focuses on engaging muscles and creating opportunities for movement throughout the day. Things like pushing, pulling, climbing, and deep-pressure activities help regulate their energy and support overall development.

This ties closely into proprioception, which is the body’s sense of where it is in space. For many people, this awareness happens automatically. For Benji and Giulietta, it takes more intentional practice. Activities that involve resistance or whole-body movement help strengthen this sense over time and make movement feel more controlled and predictable.

Communication is another area where they’ve found their own path. Although they are non-verbal, they are far from without a voice. Through Augmentative and Alternative Communication systems, along with picture cards and visual supports, they are able to express their needs, preferences, and personalities.

What stands out most in their journey is how much can be achieved with patience and consistency. Progress might look different from child to child, and it doesn’t always follow a straight path, but it is always meaningful.

Benji and Giulietta continue to grow, learn, and connect with the world around them in ways that reflect who they are. With the right support and understanding, they are building not just skills, but confidence and independence too.