Is it permissible for my mother to delay the prayer to remove henna from her hair and then make up the prayers she missed?

Prayer is the second pillar of Islam and the first thing a servant will be held accountable for. It must be performed on time, as it is among the best deeds. What this woman is doing contravenes the law of Allah, and she must perform the prayer on time. She should remove the henna if it prevents water from reaching the hair during ablution, or wipe over it if it is light. It is not permissible to delay prayer beyond its prescribed time, for that is neglect and dereliction. Allah has warned those who do so with "Al-Ghayy" and heedlessness. This mother's adherence to prayer is confirmed due to her old age.