MultiVariant child products stock

[razor7]

Hi! I have successfully set up a multivariant products strategy, but now I need to know if each multivariant child product stock is independent from his parent. I mean, If someone buy parent A, the stock will be substracted from parent A and not populated to child A-B, and if for instance someone buys child A-B the stock will decrease from child A-B and not from parent A.

Thanks in advise!