Complex sentence: However, in "Casper's Scare School", they are nice to Casper and care for him and, when Casper leaves for Scare School, they spend most of the time he's gone crying.
Split into simpler sentences: However, in "Casper's Scare School", they are uncharacteristically nice to Casper and they are shown to care for him. In fact, when Casper leaves for Scare School, they spend most of the time he's gone crying.