Since you didn't give a birthdate or birthplace for Sarah, it's kind of hard to know where to start tracking her. However, you said Sarah was married in Hopkins, Texas in 1867 and I did find a Sary C. Grace living in Hopkins, Texas in 1850. Could this be your Sarah F. Grace?
1850 4th Judicial Dist., Hopkins, Tx. Dwelling #174 George W. Grace, age 58, b. 1792 Tn., farmer Martha J. Grace, wife, age 52, b. 1798 N.Carolina James Grace, son, age 30, b. 1820 Tn Matilda Grace, daug, age 19, b. 1831 Il. Mary Grace, daug, age 14, b. 1835 Tn Sary C Grace, daug, age 10, b. 1840 Ark. George Will Ger Grace, age 7, b. 1843 Ark. Riley Grace, age 4, b. 1846 Ark.