30 parts Ongoing The Force can choose anyone. This is well-known among Jedi. Within some species, Force-sensitivity is more common than within others, but there is no sentient species - not even past the furthest reaches of the galaxy - that has never had a single Force-sensitive to some degree.
This, of course, means that every so often a Sithspawn child is born with the Force. They call her Estai and they pass her to the Jedi when she's of age.
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Introverts don't make friends. They get adopted by extroverts. With less than a decade to his name and a temper that worries his teachers, Obi-Wan wouldn't exactly call himself an extrovert, but he reacts strongly to basic displays of kindness and Estai is nothing if not kind.