Jami` at-Tirmidhi 1980
جامع الترمذي#1980Da'ifAbudullah bin 'Amr narrated that the Messenger of Allah said:"No supplication is more readily responded to, than the supplication made for someone who is absent
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirDaif
Al-AlbaniDaif
Bashar Awad MaaroufDaif
Zubair Ali ZaiDaif
In-book reference: 27:86