Will we know each other in heaven? Most assuredly! The apostle Paul said concerning heaven, “For now we see through the glass darkly; but then face to face: but now I know in part; but then shall we know even as also we are known” (1 Corinthians 13:12).
In heaven our knowledge shall be vastly superior to our knowledge here upon this earth. Do we know each other upon this earth? We most certainly do. Surely we shall be wiser there than we are here.
Furthermore, when Jesus was with Peter, James, and John on the Mount of Transfiguration, there appeared with him Moses and Elijah. They had long since been dead, so the disciples had never seen or known them (Matthew 17:1-6). However, without any introduction and without the benefit of photographs, they immediately recognized them. This suggests that in heaven our knowledge will be so superior to earthly knowledge that introductions will not even be necessary. We will not only know our loved ones, but we will automatically know everyone else also.
The Bible also teaches that our resurrection bodies will be like the glorious body of our Lord Jesus (Philippians 3:20-21). Did the disciples recognize Jesus when he came out of the grave? Yes, except on those occasions when he purposely blinded their eyes momentarily. They knew who he was and could touch the nail prints in his hands and trace the gash from the spear in his side. They knew that it was the same Jesus. There is too much overwhelming evidence to doubt that we shall know each other in the life to come.