For as long as 12 year-old Heidi (Talitha Bateman) can remember, her mentally challenged mother has had only 22 words in her vocabulary. She and Mama live happily, in the bubble of love and protection provided by their neighbor (Alfre Woodard). Then one day a new word pops out of Mama's mouth, and it propels Heidi on a solo cross-country journey of discovery, loss, truth and identity, as she finally learns who she is and where she comes from. SO B. IT is a tale of longing and family lies, of heartbreak and personal courage with just a touch of magical whimsy.