Gabriel is the second oldest, they are quite complacent in Lucifer’s behavior and given into Lucifer’s various demands. Gabriel is Non-Binary and goes by They/Them. 

Gabriel always made excuses for Lucifer, even if they were heinous. Gabriel does not get along with Michael as Michael forces them to forget about Lucifer. 

They are a worry wart, as they worry about things they aren’t supposed to be worrying about.