<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 does the voice of peter 's mom on family guy
who does the voice of peter 's mom on 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 ''