3And I heard a great voice out of heaven saying, Behold, the tabernacle of God is with men, and he will dwell with them, and they shall be his people, and God himself shall be with them, and be their God.
4And God shall wipe away all tears from their eyes; and there shall be no more death, neither sorrow, nor crying, neither shall there be any more pain: for the former things are passed away.
5And he that sat upon the throne said, Behold, I make all things new. And he said unto me, Write: for these words are true and faithful(Revelation 21:3-5).
17For, behold, I create new heavens and a new earth: and the former shall not be remembered, nor come into mind(Isaiah 65:17).
When a mother gets to heaven,or anybody else,they will not remember what happened on earth,so they cannot mourn over a loved one on earth that is lost,if they do not remember the former things.
They will be like the angels that God created that popped up one day,poof there they are,and did the angels think,how did I get here and where am I,or did they think that they always existed,but the angels know they were created.I wonder what their initial reaction was,but one thing they thought I feel good and wonderful.I do not think there is an initial reaction like how did I get here and where am I,but you will feel right at home and comfortable,like you always belonged there.
When we get to the New Jerusalem,it will be poof there we are,and we will not remember anything before that,but will only know things from that point onward,and will feel at home and comfortable like we always belonged there,and we will think I feel good and wonderful.
We will remember things concerning this earth until we get to the New Jerusalem.
The souls in heaven awaiting their brethren to join them,and all the saints that come back with Jesus when He fights the world,remember the former things.
During the millennial reign the saints remember the former things.
It is only when the saints get to the New Jerusalem that they do not remember the former things.
The only mourning a mother might do for a lost son is on this earth,prior to the New Jerusalem,for I do not know if they mourn a lost one in heaven prior to the millennial reign,or during the millennial reign,because they remember the former things,or if they have so much joy they do not mourn,but the souls under the altar in heaven ask the Lord to avenge them,so they do not like how the world behaves and deceives people,which their son would be a product of their deception and lies,for their son could of not been lost unless he believed the lies and deception of the world that go against the truth,that the saints want God to stop.