Is it permissible for my mother, who suffers severe pain when sniffing water during ablution due to her health condition, to omit sniffing and suffice with the remaining pillars of ablution?

Scholars differed regarding the ruling on rinsing the mouth and nose, between obligation and recommendation. However, according to both opinions, it is not permissible to abandon water and resort to tayammum. If rinsing the nose is recommended, the rest of the limbs must be washed. If it is obligatory, tayammum must be performed for the affected limb, and the rest of the limbs must be washed. Citing the hadith of the man whose head was wounded and then he experienced a wet dream, her prayers in the previous period are invalid, and she must make them up.