Oldest Daughter (Another Demon Sister)

Kaguya Kamado, born to Kie and Tanjuro Kamado, was always sickly. When she was born, the midwife and doctor that were present told her parents that her lungs were weak, and that she may not survive to the end of the year. She, to the relief of her parents, lived and was a happy child. Sadly, when she was 5 she contracted pneumonia, which left her bedridden for a month. Even with intense care by the village doctor and her family, Kaguya never fully recovered.
She loves her younger siblings very much, and when she's not sitting by their family's little kitchen helping her mother by peeling or chopping vegetables she can be seen sitting with the youngest children, reading them stories or rocking them to sleep as she hums the lullaby her mother would sing to her.
Though she is sick, she is happy.

Demon Slayer belongs to Koyoharu Gotouge. This is a piece of fan fiction

The cover is an edit of a different picture if ANYONE knows the original artist please tell me reverse image search isn't doing much to help me find who to credit.