Boog's learning loneliness

We're pretty attuned to Boog's cries by now. There's I'm cranky 'cause I'm hungry, cranky 'cause I'm sleepy, cranky 'cause I'm sleepy and hungry, this frustrates me, and this is pissing me off.

There's also get me out of this crib/walker/playpen/bathtub 'cause I am so done.

But lately, he's been adding this new cry. Whenever we put him down to go to sleep and walk out of the room, he has this I'm lonelly, don't leave me alone cry. You'd have to hear it. It makes your heart physically ache in your chest.

I'm not sure if this is some new 'dumb' mechanism he's evolved to help better train his parental units, or if he really doesn't want to be alone. Either way, I never realized that loneliness is something you learn. How bizarre.