Single post in Your Guide to 90%+ Breeding Pairs

Does parentage/sibling/relationship matter? Eg. User A is breeding Venonat, but wants to make a pair with specific a specific nature. User A releases eggs to the shelter, but also adopts & hatches their own eggs and releases the hatched Pokemon to the shelter User B adopts a Venonat bred by User A (with the nature User A wants) and trades it to User A User C adopts a Venonat bred by User A (and it hatches with the nature User A wants), and trades it to User A User A puts the Pokemon from User B & User C in the Daycare and gets...?