Yes

Tanjiro hesitantly goes to his mother's room expecting some sort of lecture about being a pervert. He goes inside expecting his mother mad but instead sees a wonderful sight.

"Do you find my body attractive Tanjiro? That's what your father liked too... He could never stop grabbing at my breast hehe~"

Tanjiro is in shock at what he is hearing and remains silent.

"Did I guess wrong? Perhaps my body is too ol-"

"NO! Not at all! You are our village's pride when it comes to your body, no not just your body everything about you. You are the perfect wife, the perfect mother the perfect everything!", Tanjiro blurted out as his face turns a bright shade of red.

His mother calmy smiles and grabbed Tanjiro by the hand and pulled him closer. Right on top of her. His mother's large soft breasts pressed against him. They're breathing at an increased pace. They stay in this position until his mother suddenly whispered, "Put it in Tanjiro"

Tanjiro can no longer hold himself back. He shoves his cock into his mother. His dear mother, the one who raised him. Only at this moment, those roles seemingly vanished with his mother and Tanjiro's role simply being the role of a man and a woman having sex. His mother's soft body feels like it is merging with him at every thrust. Except for his mother's soft whispers in his ears. The room was quiet the only audible sound beating the impact of skin smashing skin. His mother grabbed his head roughly and whispered in his ears, "Let's give you a baby brother..." as Tanjiro unloads his cum deep inside his mother's womb and his mother releasing a loud moan no longer caring if her daughters heard. They stay in this position for a while and eventually fall asleep.

Unbeknownst to both of them, Nezuko was secretly watching them outside the whole masturbating at the sight of her mother and brother having sex together.