Matthew remained on the floor, recognising, at least, his unfortunate, abused sister's need for dominance over this situation, at the very least. "Di... I'm... I'm sorry...! I mean, I did write about Mother's death, but it was warded private. I'm so, so terribly sorry you missed her passing -- and yes, it was my fault, for being so damned close about the matter!" He looked up at her with watery blue eyes, trying to blink back the tears even as he used them to best advantage with his soft, sweet kid sister.
"I did love our mother, with all my heart, Di. I mean, as did Father, considering he was the one who told me about Uncle Nicholas and where to reach him! He came originally to tend to Mother, you know, but...it was really too late to help her, I fear...!" He paused to consider this, with a pensively mournful look upon his face. "In fact, by the time I was writing of Mother's condition under my wards, I think it was already too late...! I mean, honestly, Di, I think losing you broke her heart!"
He couldn't understand why exactly a grimace crossed his sister's face, just then -- save possibly some form of guilt for breaking her mother's heart to that degree... "Di, I'm so sorry! I really oughtn't have said that! I mean, you had every right to avoid me, knowing from my--" He hesitated now to call them 'comrades' anymore, given what he thought about their actions, and so he finally settled on-- "that is, the other Death Eaters... that I was one of their number, myself...!" He finally stood, reaching for his sister's hand to hold. "I'm sorry! I certainly did not mean to imply that you killed Mother by disappearing from our lives..."