I'm not sure. I don't know how long after Bakemonogatari the stories concerning Araragi's sisters occur.
from reading kizumonogatari,
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when arararagi first meets her shes lost her arms and legs and ends up in a kid form. As Arararagi uses his new vampire powers to recover her limbs she grows older. Once he recovers everything she returns to her original form. Thats also where the guys on the far right are from too.