Spider is living the dream of my fantasy neurotypical self that actual me is incapable of carrying off because I’ve never had the focus or caffeine receptivity to sit in silence and read all morning (hope springs eternal, though, which is why I keep buying books and shotgunning iced coffee).
Spider’s bed is located close to where Skull’s suprachiasmatic nucleus (SCN, I’m not typing that over and over) would be, the master “biological clock” in the hypothalamus. The hypothalamus regulates sleep and mood among other things, mostly be sending hormone signals to the pituitary gland, so no wonder poor Skull is always a nervous wreck.
The external cues (eg. light, temperature) that adjust our circadian rhythms to the 24hr planetary rotational cycle are called “zeitgrebers”, a word I will now use as often as possible and suggest as a name to every pregnant person I see.
There are ambient and environmental zeitgrebers, but also social zeitgrebers (which, I mean, could technically be mostly rolled into the environmental category, but not getting that granular here). These could be things like a regular good morning or good night text, or any habitual social exchange that orients you to the time. This may be the key mechanism as to why major life changes (for good or bad) can disrupt sleep and induce depression. If the zeitgreber isn’t there, the SCN doesn’t send hormones to the pituitary gland so it doesn’t send out other different hormones elsewhere and then you’re sleeping like shit and manically trying to learn medieval bookbinding at 4am because you want to make an illuminated manuscript for the first half of the novelization of the movie Phantasm that you found on a Metallica fansite from 1997, get stoned then write the rest yourself and give it to someone you’re dating as a Christmas present while sobbing uncontrollably because you know they’re just going to abandon you like everyone else always has and why bother doing anything when you’re destined to die alone.
As a random example.
So in this, Spider is Skull’s SCN, hypothalamus, hormones, and zeitgreber all in one. They take that responsibility very seriously, no matter how many of those books are Sweet Valley Twins novels.