Arlo is Rosa Diaz’s dog.
Throughout the Series[]
Season Three[]
In 9 Days, Rosa originally got the dog as a replacement for Charles's own dog Jason who had died. Charles rejected Arlo, leaving him in Rosa's care. After caring him for only a day and a half, Rosa stated to the squad that if anything happened to him, she'd kill everyone in the Nine-Nine and then herself.
Season Five[]
In The Big House Pt. 1, Rosa asked Raymond Holt and Terry Jeffords to bring Arlo to Adrian Pimento's ranch in Argentina.
Season Seven[]
In Valloweaster, Rosa mentions Arlo when noting Cheddar's appearances in the precinct and points out she never brings Arlo. Jake doesn't know who she's referring to by the name Arlo.
Images[]
Behind the scenes photograph of Joe Lo Truglio playing with the puppy on set
Candid photo of Stephanie Beatriz in costume as Rosa Diaz on set snuggling the puppy who plays Arlo
Brooklyn Nine-Nine Writer & Producer, Justin Noble with Arlo
Fan Art by by Freelance Illustrator user - lou_quorice on X