The problem with counting the number of products.

[VopoloS]

• I add a parent product with stock =0 and add to it different child products with stock >1. In this case, I can't put child product in the cart!
• 
  I add the parent product with the balance in stock =3 and add to it various subsidiary items (child products)  in stock 2 >1. In this case, can I put child product in the cart in number of 3 units!
  

And now attention! What is the number in stock to specify the parent item?