All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu 'alyhi wa sallam, is His slave and Messenger.
In the Barzakh, all the souls of the believers will meet and know each other; however, the way they will meet is different from that of this life. The norms of life in Barzakh are unlike the norms of this worldly life, since it is a part of the Unseen and its reality is known to Allaah The Almighty alone.
Scholars had more than five different views about the abode of the souls after death. Ibn Al-Qayyim listed these views and preferred the view that there is no certain abode for the souls and that they stay in several places. Some of these souls stay in graveyards, others are in Paradise, others are kept at the doors of Paradise and others roam free. Nevertheless, it is possible for the soul which is in Paradise to meet the soul that is in the graveyard because the souls have their specific characteristics that do not conform to that of humans.
Proof of this is that in this world the souls of the dead and those of the living meet each other, although the former are in the Hereafter while the latter are still in this world, yet they still meet. In this regard, Allaah The Almighty Says (what means): {Allaah takes the souls at the time of their death, and those that do not die [He takes] during their sleep. Then He keeps those for which He has decreed death and releases the others for a specified term. Indeed in that are signs for a people who give thought…} [Quran 39: 42]
In his interpretation of this verse, Ibn Katheer mentioned that it indicates that the souls meet in the exalted assembly [of angels]. There is also a Hadeeth on the authority of Abu Hurayrah where the Prophet, sallallaahu ‘alayhi wa sallam, instructed us to say the following supplication at bedtime: “Bismika Rab-bi wadha‘tu janbi wa-bika arfa‘uhu, in amsakta nafsi farhamha wa-in arsaltaha fahfath-ha bima-tahfathu bihi ‘ibaadak as-saaliheen (In Your name, my Lord, I lay down my side and in Your name I raise it up; if You take my soul, have mercy on it, and if You send it back, protect it with which You protect Your righteous servants).” [Al-Bukhari and Muslim]
Some of the righteous predecessors mentioned that Allaah The Almighty takes the souls of the dead upon their death and the souls of the living during their sleep and that they meet for as long as Allaah The Almighty wills.
Allaah Knows best.