Fostered by Ælfwynn wife of Æthelstan Half-King together with her son Æthelwine, Edgar enjoyed the support of Æthelstan Half-King (d. after 957) and his sons, whose power base was concentrated in Mercia and East Anglia and who would not have liked to lose power and influence to Ælfgifu's kinsmen and associates.
Diasuh oleh istri Ælfwynn Æthelstan Setengah-Raja bersama-sama dengan putranya Æthelwine, Edgar menikmati dukungan Æthelstan Setengah-Raja (wafat setelah tahun 957) dan putra-putranya, yang kekuatan basisnya berkonsentrasi di Mercia dan Anglia Timur dan tidak akan gembira kehilangan kekuasaan dan pengaruh pada kerabat dan asosiasi Ælfgifu.