Bart is the fourth child of Bart Allen and Cissie-King-Jones.
Bart was born in the 30th century of an alternate Earth to Meloni Thawne and Don Allen. However, when that universe collapsed, Don Allen crossed into the main universe and left their Bart with Max Mercury. Max, feeling he was too old for the responsibility, asked Bart and Cissie to take the younger Bart in. They agreed. Bart was given falsified documents with a birthname of Bart Allen-King-Jones III and a birthdate of August 18, 2020. He's affectionally referred to as Bat.
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Bat possesses similar Speed Force powers to his father/counterpart, Bart.
Bat is the youngest (so far) member of the second generation of Young Justice. He looks up to his older siblings, especially Max.
Bat's best friend is Elly Kent.
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Bat's PB is Oliver Davis.