Browning, Charles H. Americans of royal descent, 7th ed., 1986. Baltimore : Genealogical Pub. Co., pg. 84 gves name as "Chetwode." Her ancestors back to Henry III, King of England given in Browning, pg. 391-392. 411, 498.
Grace Chetwood was born about 1602 (aged 33 or 30 in 1635), "a virtuous daughter of Sir Richard Chetwood." She married the Rev. Peter Bulkeley in April 1635 as his 2nd wife, and came to Massachusetts Bay with him & her stepchildren in 1635 on the "Susan & Ellen." They first settled in Cambridge MA & later moved to Concord MA.They had four children: Gershom, Eleazer, Dorothy, & Peter.
She died at New London 21 Apr 1669, widow of the "sometime Pastor of the ch[irc]h of Concord, deceased. She was a woman of great piety and wisdom & died in good old age. Her sickness was long and very afflictive. She was sick near 3 months before she died. she had not the use of her understanding but by fits, the greatest part of her sickness" (findagrave.com)