'Mother's' in the Bible

and Abimelech son of Jerubbaal goeth to Shechem, unto his mother's brethren, and speaketh unto them, and unto all the family of the house of his mother's father, saying,

And his mother's brethren speak concerning him, in the ears of all the masters of Shechem, all these words, and their heart inclineth after Abimelech, for they said, 'He is our brother;'