Much remembered his brother, although he never spoke of him.
He had often been left in charge of Michael while their parents worked the mill. He was quite young to be watching a child barely out of infancy; yet, he felt that he had found his purpose, and cared for the boy as best he could. Then, the sickness came through, and stole them all away within days of each other; nobody knew how it spared Much. Devastated, he mourned his parents-- but took it as a personal failure that Michael succumbed. He'd thought he'd known what he was meant for; apparently, he was wrong. Perhaps, he had no purpose.
When the Earl of Huntingdon took on Much to look after his heir, it seemed as though he was being given a second chance. Not that his new master could ever replace his brother, but if he could just keep Robin safe, then maybe he had meaning, after all.
Over the years, he came to be aware of who he was, and that he was more than just a servant. He understood and appreciated that he had purpose and needs unto himself. He knew that Michael's death was not his fault. He forgot his father's voice, his mother's scent.
However, he remembered Michael's bright, blue gaze.
So, when Little John took him aside one day and asked why he stayed with Robin when his former lord so often took him for granted, Much thought of his brother. Caring for Robin was not his reason for being, but he enjoyed doing it. And when Robin put on freshly-washed clothing, or enjoyed a good meal, Much somehow felt that Michael was with him. He knew it was silly, which was why he never mentioned it.
Still, on those nights when Robin went to bed content because of what he had done, Much would close his eyes and see his brother's smile, and any hurts or disappointments of the day melted away.
He did it for Michael.