Danny Reagan (Donnie Wahlberg) is one of the children of Police Commissioner Frank Reagan (Tom Selleck) in the series Blue BloodsAlready it's been ten years since audiences were introduced to the fiery-tempered, yet loyal and good-hearted character.

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Danny, like the majority of his family, has a career in law enforcement and never backs down from a challenge, always seeking justice. He loves his family and protects them fiercely, and though audiences know plenty about him, there are a few surprises they may have overlooked.

His Partner Wasn't Always Maria Baez

Danny and Maria have been partners for some time, but prior to Season 3, Danny had other partners. Most significantly was Jackie Curatola, played by Jennifer Esposito, who lasted the longest.

Danny had a different partner in "Pilot", named Demarcus King; Danny was also briefly partnered up with Ava Hotchkiss, Kate Lansing, and Candice McElroy; Danny struggled to get along with Ava, and Kate helped Danny out of a jam in Season 3 before she left. Danny and Maria are great together, with some fans hoping for a romance between them, but it took Danny a bit to get the perfect partner for him.

Danny Was Nearly Jailed

Danny being escorted through his precinct after his arrest in Framed Blue Bloods

So many things have happened on Blue Bloods in the past decade that it's easy to forget some of the things that happened to the main characters over the years. One such incident occurred in the Season 3 episode "Framed", in which cocaine was found in Danny's Jeep and he was placed under arrest.

As it turns out, he was investigating a case that was getting dangerously close to revealing the fact that Captain Derek Elwood, who interviewed Danny, had set him up, as he owed a significant amount of money to the bookie that was shot, and who was a part of Danny's investigation.

He Helped Out Eddie

Eddie holding a coffee cup in Blue Bloods

In a Season 9 episode, Danny told Eddie about what happened to Joe, their brother, who was killed prior to the events of Season 1. Danny advises her on how Jamie thinks, and offers to talk to Jamie on her behalf, with her permission, of course, given Jamie is hesitant to let Eddie join a fraternal organization.

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It undoubtedly brings back bad memories for Jamie, who investigated The Blue Templar in Season 1, the organization responsible for Joe's murder. Danny proves he's a good brother-in-law in this episode by supporting and helping Eddie, and Jamie, by extension.

His Middle Name Is Fitzgerald

Danny laughing in Blue Bloods

Knowing Danny, this seems like it wouldn't suit him too well, but it's still his middle name, nonetheless. It's not mentioned every episode, so this is easily a bit of trivia about Danny that audiences missed.

Danny has a penchant for landing in hot water; maybe his parents Frank and Mary knew from the get-go that that was to be expected from their son and thus gave him a three-syllable middle name to make things more serious and intense when calling their son out by his full name.

He Didn't Always Want To Be A Cop

Danny looking serious in Blue Bloods

Surprisingly yes, even the devoted Detective Danny Reagan had considered another career path at one time. In a story Danny recalled, he wanted to go as a firefighter one Halloween when he was little, and his grandfather, Henry (Len Cariou) immediately put a stop to that. Instead, Henry gifted his grandson with a police uniform, and the rest is history.

Danny Accidentally Traumatized His Niece

Danny and Nicky talking and sitting at a table in Blue Bloods

Danny was trying to help his niece, Nicky, in a Season 1 episode with a homework assignment, and he happens to get a call to a crime scene. Nicky pleads with him to take her along, and he reluctantly does so, giving her the strict order to stay in the car and wait. A curious Nicky disobeys and sees her first dead body, which gives her severe nightmares.

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Erin isn't too happy with her brother for exposing Nicky to a crime scene at a young age, and though it was unintentional, Danny scarred his niece that day and forced her to deal with something very adult for her young age.

Danny Overlooks His Personal Life Too Often

Danny and Linda on Blue Bloods

Donnie Wahlberg agrees that his character is somewhat negligent when it comes to any problems in his job or his personal life. Danny is focused on getting the job done, but he tends to overlook his own personal woes, especially since losing his wife Linda. Fans, like Danny, may get wrapped up in his cases and forget that he's dealing with some serious things in his life.

In an interview, Wahlberg mentioned that he'd like to see Danny deal with some of his past trauma in the upcoming eleventh season, and that could definitely mean new storylines and opportunities to explore the character in a new way the show hasn't before.

Danny Keeps An Interesting Picture On His Desk

Danny in his police uniform Blue Bloods

According to Wahlberg's Instagram, he's kept a picture of none other than Tracy Morgan, decked out in police uniform in an 8x10 photograph, on Danny's desk for the past nine seasons. It's an interesting choice instead of Donnie's real-life wife Jenny McCarthy, or even pictures of Danny's family, but it definitely stands out, and audiences will no doubt look for a glimpse of it the next time they catch an episode of Blue Bloods.

Donnie Wahlberg Dropped Music References In Danny's Speech

Danny wearing a hat in Blue Bloods

Donnie Wahlberg is a member of New Kids on the Block, a boy band that began in the 1980s. Wahlberg mentioned that he would "sneak" a song title from New Kids on the Block in each episode back in the first season.

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He listed a few examples, in which he would tell Bridget Moynahan's character things like "hey, hang tough" and "call it what you want", for instance. If fans listen closely to Danny's remarks in the first season, they're bound to pick up the references to New Kids on the Block. 

Danny's Calmed Down

Danny in Blue Bloods with a small smile

It's definitely true. Considering in the pilot episode, Danny's interrogation technique was seriously brutal, even shoving the suspect's head in the toilet and beating him up somewhat. Danny is passionate about his work, and in the "Pilot", he was searching for a missing girl and he had a deadline, so that especially decreased his patience for any antics the suspect had in mind.

He hasn't shoved anyone's head in a toilet lately, and he does still lose his temper on occasion, but compared to when audiences first met Danny, he's calmed down significantly, probably due to wisdom in lessons learned.

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