Mildred f
English: 19th-century revival of the Old English female name Mildpryð, composed of the elements mild gentle + prỹð strength. This was the name of a 7th-century abbess, who had a less famous but equally saintly elder sister called Mildburh and a younger sister called Mildgyð; all were daughters of a certain Queen Ermenburh. Their names illustrate clearly the Old English pattern of combining and recombining the same small group of name elements within a single family.
First names dictionary. 2012.