First, we need to determine how many siblings Billy has. To do this, we perform 2*2= <<2*2=4>>4 brothers, as he has 2 sisters and twice as many brothers as sisters.
Then we divide the total number of sodas in the 12 pack, which is 12, by the number of siblings, performing 12/6=<<12/6=2>>2 cans per person.
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