User blog comment:Salubri/New Characters and Reveals in the Future of Bleach/@comment-1774413-20100828145410/@comment-44061-20100828150518

Did we we know of their pasts as Captains and had minor flashbacks of Yoruichi's life but we know virtually nothing about her beyond that or her family and we only have mention of her and Urahrara's past. Its not enough to assume that being in the Gotei 13 was just the beginning of their existence