What is the importance of the teepee that Sequoyah and Harold build in the novel, Where the Dead Sit Talking?

As the narrative draws to its conclusion, the teepee that Sequoyah and Harold build becomes a symbol of Sequoyah's reaching to find and claim a new sense of identity. On one level, that identity involves experiences of solitude, the value of which Sequoyah encountered as a result of his experiences of solitude with Rosemary and Harold. For him, the teepee is where he experiences solitude entirely on his own terms: when he experienced it in the attic, it was still part of his life (i.e. his home environment) with the Troutts. The teepee is perhaps not precisely or entirely independent: it represents, however, significantly more independence.

On another level, the teepee also represents Sequoyah's embracing and valuing of his ethno-cultural heritage - specifically, his Indian-ness. A teepee is a dwelling with a specific shape and construction specific to Indians in North America: in claiming a teepee as his place of solitude and refuge, Sequoyah is also claiming a sense of himself that up to that point he had been reluctant to fully engage with. The fact that the teepee becomes his place of solitude - where he literally engages with himself, alone on his own terms - suggests that as he becomes more comfortable with himself in general, he is also becoming more comfortable with the specific, Indian-defined side of his identity.