Mary was left at home, while Martha went out of the town to meet Christ. It seemeth by this verse, Christ had asked for her, though that be not mentioned before. Martha goeth secretly to her, and tells her that the Master was come. (It was a name they usually called their most famous teachers by).
Related Commentaries of John 11:28
John 11:28
28 And when she had so said, she went her way, and called Mary her sister secretly, saying, The Master is come, and calleth for thee.