The Miswaak Twig

Q: Imaan-112 : Which twig is to be used for the Miswaak when making wudhu? Will it suffice to perform Tayammum before sleeping at nights and in the afternoons? On which side is it Sunnah to sleep?

Answer: It is permissible to use the twig of any tree as a Miswaak when making wudhu. However. it is best to use twigs that have a bitter taste because these are more beneficial. The best will be the twig of the Peelu tree.
Although it is best to perform wudhu before sleeping at nights and in the afternoons, one may also perform Tayammum.

When lying down to sleep. one should lay on the right side while facing towards the Qibla. Thereafter, it is permissible to lay on either side. And Allaah knows best what is most correct.

Fatawa Rahimmiyyah (vol. 1)