Investment in associates

Hello
Wanted to clarify, for the following journal entries relating to intra-group trading between parent and associate, what AMOUNT is supposed to be debited and credited?:

If A sells to P:
Dr. Group retained earnings (CSOFP)/ P’s share of A’s profit (CSOPL)
Cr. Group inventory

If P sells to A:
Dr. Group retained earnings (CSOFP)/ cost of sales (CSOPL)
Cr. Investment in associate

Also, for the second journal entry why do we debit cost of sales when inventory is included within the associate’s closing inventory and not the parent’s?