I am writing to formally request a leave of absence from [start date] to [end date] due to my mother's serious illness, which requires my immediate attention and care. Her medical condition has necessitated hospitalization, and as her primary caregiver, I need to be present to assist with her treatment and recovery leave application for a mother illness.

I kindly request approval for [number of days] days of leave under the company's compassionate or sick leave policy. I will ensure all pending tasks are either completed or delegated to [colleague's name] before my leave begins. For urgent matters, I will remain available via email or phone during this period.