9 Month Developmental Stage

The key phrase this month is: SEPARATION ANXIETY
The definition of SEPARATION ANXIETY: scream and cry as loud as possible whenever either/both parent(s) leave the room; do this even if you are still able to see them; increase intensity of screaming and crying as the amount of daylight decreases.
The definition of SEPARATION ANXIETY, modifier WITH TWINS: if our sibling is screaming and crying by all means, join in.