Younger brother of Arthur Wahlberg, Donnie Wahlberg and Robert Wahlberg. His older siblings are: Arthur Wahlberg, James Wahlberg, Debbie Wahlberg, Michelle Wahlberg, Paul Wahlberg, Tracey Wahlberg, Robert Wahlberg and Donnie Wahlberg. Robert, Donnie and Mark are from their mother's third marriage with Donald Wahlberg.
United States Marine (Veteran) Daniel Fitzgerald âDannyâ Reagan is the oldest child of Frank and Mary Reagan, and the older brother of Erin, Joe, and Jamie Reagan. Danny is an investigator of New York City's 54th Precinctâs Detective Squad, specializing in Major Crimes, and doing what needs to be done to serve justice in the fight against crime.
From 2002 to 2003, he starred in the crime drama Boomtown. He has been starring in the drama series Blue Bloods as Danny Reagan with Tom Selleck (his TV father) and Bridget Moynahan (his TV sister) since 2010, and since 2014 is an executive producer of the TNT reality television show Boston's Finest.