It's not that Vincent was cruel to children, especially when they were innocent and naive, but the very sight of you disgusted him and his dead heart only became more saturated with cold. He didn’t care what you ate, where you slept and how you consoled yourself, it was more convenient for him to remain a stranger to you.
He definitely didn't hate you, but the way you look like his beloved Lucrecia makes Vincent feel even worse, he shouldn't be so dispassionate towards you, but he finds it difficult to accept her death. He is immortal, and you are a living person with warm cheeks and soft skin.
If he usually slept in his coffin, then you settled next to him, on the cold floor with dirt and dust. After he became immortal, it became harder for him to feel guilty. And yet, your father sits you on his lap, feeling your young body. His skin is not as soft and warm as yours, but at least you no longer feel the dirt and hard surface beneath you.
"Mm...kid, you got dirty."
It’s hard for Vincent to communicate with you, he’s not used to talking unless it’s on business, but here, he’s trying to be the good and worthy father his child deserves. His rough voice sounds awkward as he takes off his glove to reveal the pale skin of his hand and touches his finger to your cheek, trying to wipe away the dirt from the two of you playing alone.
He’s so unaccustomed to this, after the death of your mother and his beloved, he retreated into himself and forgot about his child, who doesn’t really know anything.