<P> Several recurring characters appeared in the first season . Amy Carlson appeared as Linda Reagan , Danny 's wife and mother of two children Jack and Sean . Sami Gayle portrayed Erin 's teenage daughter Nicole `` Nikki '' Reagan - Boyle ( Marlene Lawston played this role in the pilot episode ) . Abigail Hawk portrayed Abigail Baker , Frank 's primary aide . Brothers Andrew and Tony Terraciano portray Sean and Jack Reagan , Danny and Linda 's sons . Gregory Jbara acted as Garrett Moore , the NYPD 's Deputy Commissioner of Public Information . Robert Clohessy played Sgt . Sidney Gormley , the immediate supervisor of Danny and the other detectives at the precinct . Actress Dylan Moore appeared in the first six episodes as Jamie 's brief fiance Sydney Davenport . Bruce Altman portrayed Mayor Frank Russo , Frank 's superior . Andrea Roth appeared in four episodes as Kelly Davidson , a television news reporter who dated Frank . Yvonna Kopacz Wright portrayed Ava Hotchkiss , a detective at the precinct and Danny 's temporary partner . Noelle Beck appeared in three episodes as Frank 's Deputy Press Secretary Sue Connors . Nick Sandow recurred in four episodes as Lieutenant Alex Bello , an officer at Internal Affairs . Michael T. Weiss portrayed Sonny Malevsky , a detective who had worked with Joe Reagan before his murder . Colleen Clinton appeared as Agent Anderson , an FBI agent who attempts to recruit Jamie for her investigation into the Blue Templar . Bobby Cannavale appeared in three episodes as Charles Rosselini , Erin 's boss who becomes romantically involved with her . Robert John Burke portrayed Jyle Hogan in three episodes . </P>
<P> Several recurring characters appeared in the first season . Amy Carlson appeared as Linda Reagan , Danny 's wife and mother of two children Jack and Sean . Sami Gayle portrayed Erin 's teenage daughter Nicole `` Nikki '' Reagan - Boyle ( Marlene Lawston played this role in the pilot episode ) . Abigail Hawk portrayed Abigail Baker , Frank 's primary aide . Brothers Andrew and Tony Terraciano portray Sean and Jack Reagan , Danny and Linda 's sons . Gregory Jbara acted as Garrett Moore , the NYPD 's Deputy Commissioner of Public Information . Robert Clohessy played Sgt . Sidney Gormley , the immediate supervisor of Danny and the other detectives at the precinct . Actress Dylan Moore appeared in the first six episodes as Jamie 's brief fiance Sydney Davenport . Bruce Altman portrayed Mayor Frank Russo , Frank 's superior . Andrea Roth appeared in four episodes as Kelly Davidson , a television news reporter who dated Frank . Yvonna Kopacz Wright portrayed Ava Hotchkiss , a detective at the precinct and Danny 's temporary partner . Noelle Beck appeared in three episodes as Frank 's Deputy Press Secretary Sue Connors . Nick Sandow recurred in four episodes as Lieutenant Alex Bello , an officer at Internal Affairs . Michael T. Weiss portrayed Sonny Malevsky , a detective who had worked with Joe Reagan before his murder . Colleen Clinton appeared as Agent Anderson , an FBI agent who attempts to recruit Jamie for her investigation into the Blue Templar . Bobby Cannavale appeared in three episodes as Charles Rosselini , Erin 's boss who becomes romantically involved with her . Robert John Burke portrayed Jyle Hogan in three episodes . </P>
who plays nikki in season 1 of blue bloods
who plays nikki in season 1 of blue bloods
Sami Gayle
Sami Gayle