Almost 13, Jessie is Isa’s twin and the pragmatic, scientific thinker among her siblings, who becomes an organized planner for the garden project despite initial skepticism.

At seven years old, she is the empathic and imaginative sibling, intuitively connected to nature and people, influencing the family’s project with her emotional insight.

The five-year-old youngest sibling, whose innocent and direct actions significantly impact the family endeavor, driven by love and a literal understanding of the world.

The Vanderbeekers’ once-reclusive landlord, whose initial detachment slowly transforms through interaction with the children and their garden, reconnecting him with the community.

Initially Oliver’s rival, Herman evolves from a seemingly privileged boy to a valued participant in the garden project, revealing deeper layers through newfound friendships.

The warm-hearted second-floor neighbors whose crisis motivates the children’s garden project; Miss Josie provides inspiration while Mr. Jeet’s well-being becomes central to their efforts.

Herman’s father and the story’s antagonist; his focus on financial pragmatism and urban development poses a threat to the community’s garden project.

Jessie’s twin sister, who is away at orchestra camp but remains a source of stability and wisdom, offering support and perspective to her siblings from a distance.

The supportive, loving parents of the Vanderbeeker family, whose values resonate in their children’s community-focused actions, despite being preoccupied with personal and work-related challenges.