Eliot and Margo make fun of Alice for her apparent advantages while Quentin sits by in episode 1x01 "Unauthorized Magic". Quentin calls Julia on the payphone and leaves a message in episode 1x02 "The Source of Magic". Alice calls her parents and learns about Joe's suicide in episode 1x11 "Remedial Battle Magic". Appears in 4 more episodes.
Source: Chris Fisher — Instagram
Eliot travels back to a high school memory with Charlton where he used his magic for the first time and killed a kid in episode 4x05 "Escape from the Happy Place".
Niko calls Mel about meeting for lunch and later Mel tries to get Niko out of the building while she is under the influence of the truth serum in episode 1x02 "Let This Mother Out".
Maggie finds Brian at his work and tells him that she only wishes to be friends in the future in episode 1x02 "Let This Mother Out". Mel freezes time to watch Niko only to realize that Niko is still wearing the magic-blocking ring she gave her in episode 1x22 "The Source Awakens".