(This is NOT a theory of RJ)

In S05E05 Red Dawn, when Hannigan moved to another unit, there was a quick scene with the profile of GVP. I tried getting the text out of her bio, so here's what I have (some words are unknown, referred to as ???? because the text was so small to read):

"Van Pelt is from a small farming town in Iowa. She tends to be overly sensitive at times, but is very intelligent. Van Pelt works with Det. Chillings most of the time, but occasionally works with the FBI or SFPD. She is the gold standard of the team, having started her job in the year 2000. Grace's cousin is supposedly a psychic, causing her to sometimes argue about matters of faith. In the case of 788728-009, the suspect made a remark about Van Pelt's character, stating "...you're deeply depressed and emotionally shut down...because of a trauma in your past that you've never spoken with anyone...ever...even yourself..." which Van Pelt's facial expression seems to confirm. In the case 459959-001 she is ???? for ???? due to a killer who is killing red haired people, leading her to being in an uncomfortable situation"

- The psychic was her cousin Yolanda
- The trauma referred to is probably Van Pelt's sister which she lied about to Rigsby (S02E10 Throwing Fire)
- The serial killer part is very interesting