<Li> Thelma Griffin ( voiced by Florence Stanley in the first appearance , Phyllis Diller in later appearances , Alex Borstein as a young woman in `` Do n't Be a Dickens at Christmas '' ) -- Ex-wife to Francis , mother of Peter , and paternal grandmother of Meg , Chris , and Stewie . She is the mother - in - law of Lois . She first appears in `` Holy Crap '' . She is 82 years old as stated in the episode `` Mother Tucker '' , has gray hair and noticeable wrinkles below her eyes , and wears purple earrings and a purple bead necklace . She also wears glasses like her son and husband and is a heavy smoker . Unlike Francis , she is generally friendly and personable , and gets along well with Lois . Before Francis ' death , she divorced him because she had `` needs he did n't fill '' and dated Tom Tucker for a while in `` Mother Tucker '' . She often appears with news inconvenient or troubling to Peter and his family . Her brief partnership with Peter 's biological father , Irishman Mickey McFinnegan , is only established in the episode `` Peter 's Two Dads '' . In the episode `` Grumpy Old Man '' , it is revealed that Thelma was sent to a retirement home . In the Season 12 episode `` Mom 's the Word '' , it is revealed that Thelma died from a stroke . Thelma 's death was written into the series because of Phyllis Diller 's own death in August 2012 . </Li>
<Li> Thelma Griffin ( voiced by Florence Stanley in the first appearance , Phyllis Diller in later appearances , Alex Borstein as a young woman in `` Do n't Be a Dickens at Christmas '' ) -- Ex-wife to Francis , mother of Peter , and paternal grandmother of Meg , Chris , and Stewie . She is the mother - in - law of Lois . She first appears in `` Holy Crap '' . She is 82 years old as stated in the episode `` Mother Tucker '' , has gray hair and noticeable wrinkles below her eyes , and wears purple earrings and a purple bead necklace . She also wears glasses like her son and husband and is a heavy smoker . Unlike Francis , she is generally friendly and personable , and gets along well with Lois . Before Francis ' death , she divorced him because she had `` needs he did n't fill '' and dated Tom Tucker for a while in `` Mother Tucker '' . She often appears with news inconvenient or troubling to Peter and his family . Her brief partnership with Peter 's biological father , Irishman Mickey McFinnegan , is only established in the episode `` Peter 's Two Dads '' . In the episode `` Grumpy Old Man '' , it is revealed that Thelma was sent to a retirement home . In the Season 12 episode `` Mom 's the Word '' , it is revealed that Thelma died from a stroke . Thelma 's death was written into the series because of Phyllis Diller 's own death in August 2012 . </Li>
who plays peter 's mom in family guy
who plays peter 's mom in family guy
Florence Stanley in the first appearance Phyllis Diller in later appearances Alex Borstein as a young woman in `` Do n't Be a Dickens at Christmas ''
Florence Stanley in the first appearance Phyllis Diller in later appearances Alex Borstein as a young woman in `` Do n't Be a Dickens at Christmas ''