<P> Frank married Mary Margaret Reagan in the early 1970s , and they have four children together : Danny , Erin , Joe , and Jamie . Each of Frank 's sons followed him into the NYPD : Danny ( Donnie Wahlberg ) is a Detective 1st Grade and lead investigator with the 54th Precinct 's Detective Squad ; Joe was a Detective with the Warrants Squad who was murdered on the orders of his partner Sonny Malevsky ( Michael T. Weiss ) , the leader of a corrupt gang of police officers called the Blue Templar ; and Jamie ( Will Estes ) is a patrol officer assigned to the 12th Precinct with a law degree from Harvard University . Frank 's only daughter , Erin ( Bridget Moynahan ) , is also in law enforcement as a Manhattan Assistant District Attorney . Erin was promoted to Deputy Bureau Chief of the NYCDA 's Trial Bureau in 2013 . </P>
<P> Frank married Mary Margaret Reagan in the early 1970s , and they have four children together : Danny , Erin , Joe , and Jamie . Each of Frank 's sons followed him into the NYPD : Danny ( Donnie Wahlberg ) is a Detective 1st Grade and lead investigator with the 54th Precinct 's Detective Squad ; Joe was a Detective with the Warrants Squad who was murdered on the orders of his partner Sonny Malevsky ( Michael T. Weiss ) , the leader of a corrupt gang of police officers called the Blue Templar ; and Jamie ( Will Estes ) is a patrol officer assigned to the 12th Precinct with a law degree from Harvard University . Frank 's only daughter , Erin ( Bridget Moynahan ) , is also in law enforcement as a Manhattan Assistant District Attorney . Erin was promoted to Deputy Bureau Chief of the NYCDA 's Trial Bureau in 2013 . </P>
who plays linda reagans brother on blue bloods
who plays linda reagans brother on blue bloods
Donnie Wahlberg Will Estes
Donnie Wahlberg Will Estes