The true law that governs marriage.

Many on earth think that families will be reunited here and then go on in the same relation as before, perhaps to all eternity, but this is not so, neither does any family ever sustain the same relationship that it sustained while on earth.

For instance, we will say a family on earth has two or three small children translated to the celestial world, the father and mother and the remaining children live on earth for a great many years thereafter, the children thus remaining grow to manhood and womanhood, marry, and have families of their own, the father and mother remain, perhaps, fifty or more years; we will say that perhaps the children they lost have been in the celestial world fifty years. Now these children have not been standing still; no, not for a moment—no more than those on earth. If those on earth have grown to manhood and womanhood and married, can anyone think that those in the celestial world have not done the same. It must be a self-evident truth that such is the case. These celestial children have also grown to manhood and womanhood, they have been united to their true counterparts, and the union constitutes an angel or completed whole, male and female as one. They do not bear children, as on earth, but the union of the positive and negative forces, male and female generates thought, and thoughts are things; that is, an angel's thoughts become objective, or objects—spiritual entities—not human spiritual or angelic living entities endowed with life and motion but thought entities. 

Herr Franz in Letters from the spirit world