Title refers to the quote from the Clockwork Angel book - "pulvis et umbra sumus."
Magnus reveals his mother's suicide after she discovered she bore a demon's child.
The characters Iris, the nurse Leigh, and Madzie were named after the episode writer's nieces and/or goddaughters, and the name of one of the warlocks shown in the Institute database records, Floretta Camp, is a mixture of his grandmothers' names.
The title is derived from "we are but dust and shadows", which is translated from the line "Pulvis et umbra sumus" by Roman poet, Horace.
One of the warlock marks considered for the newborn baby was having goat feet, for which a prop was made and used in a take but was ultimately not included in the episode.