Under William's fourth son, King Henry I of England, the Normans, now well established in England, responded by pushing west into Wales. This time, both the Welsh and the Normans were more interested in making peace than fighting bloody battles, and a relatively stable situation developed, although the Normans fared worse in southeast Wales than in the west of the country. The standoff continued from 1135 to 1154 under Stephen, King of the English, nephew of Henry and a maternal grandson of William, who became locked in a power struggle and civil war with Empress Matilda, Henry's daughter and only surviving legitimate child.