Here are her parents on her birth record and his parents on his death record.
Source: "Texas, Comanche County Records, 1858-1955," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:QGN4-LJNR
: 8 December 2017), Mollie Mary Rebecca Pierson, 22 Aug 1894; citing Birth, 22 Aug 1894, Comanche, Comanche, Texas, United States, Comanche County Clerk, Texas.
Texas, Comanche County Records
Name Mollie Mary Rebecca Pierson Female
Birth 22 Aug 1894 Comanche, Comanche, Texas, United States
Father W J Pierson Birthplace Tennessee Age 29
Mother Sarah Elizabeth Smith Birthplace Texas Age 22
"Texas Deaths, 1890-1976," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:K34B-Y96
: 13 March 2018), William Authur Mahagan, 30 Sep 1960; citing certificate number 65723, State Registrar Office, Austin; FHL microfilm 2,116,477.
Name William Authur Mahagan
Death 30 Sep 1960 Plainview, Hale, Texas, United States
Certificate Number 65723
White Male Married Farmer Age 73
Birth Date 24 Sep 1887 Birthplace , Kansas
Father Lyman Mahagan
Mother Maggie Brown
Burial October 1, 1960 Petersburg Cemetery, Hale Co., TX
Informant: Mrs Arthur Mahagan
Death cert image at: https://www.familysearch.org/ark:/61903/3:1:33S7-9B9C-Z6Y?i=953&cc=1983324