سنن أبي داود

Husain reported on the authority of the children of Sa’d b. Mu’adh that Usaid b. Hudair used to act as their Imam. (when he fell ill) the Messenger of Allah (ﷺ) came to him inquiring about his illness. They said: Messenger of Allah, our Imam is ill. He said : When he prays sitting, pray sitting.

Abu Dawud said : The chain of this tradition is not continuous (muttasil)