Rachael MacFarlane (born 21 March 1976) is an American voice actress best known for her appearances in the FOX animated series Family Guy and American Dad!, both created and executive-produced by her older brother Seth.

Some of Rachael's best known character voices include:

• The Grim Adventures of Billy and Mandy - Mindy and Eris
• Codename: Kids Next Door - Supreme Leader Numbuh 362
• Family Guy - Olivia Fuller, Meg Griffin (pilot)
• Static Shock - Nina Crocker/Time-Zone
• The Batman - Blaze

Aside from voice acting, MacFarlane has also been involved in other aspects of animation, such as being a production manager for The Grim Adventures of Billy and Mandy and Welcome to Eltingville. She also wrote an episode of Billy and Mandy, titled "Educating Grim".

On September 18, 2012, Rachael follows in her older brother's footsteps and releases a big band album entitled "Hayley Sings". [1]

Rachael is the younger sister of Seth MacFarlane, and provides the voices of Hayley Smith, Barb Hanson, and Lisa Collins on American Dad!.