Can my mother do tayammum instead of wudhu, as she is around 80 years old and there is a danger that she may fell in the Western washroom. We live in apartment building and only place she can do wudhu is in the sink, which is quite high for her height. If she is allowed to do tayammum then what she can use to perform tayammum? May Allah rewards you the most!
بسم الله الرحمن الرحيم
Tayammum is valid only when the use of water is feared to cause or increase the sickness and it is confirmed by physician or by experience. If it is not so, then tayammum is not valid. You should make arrangements for your mother to do wudhu on floor.
Allah knows Best!
Darul Uloom Deoband