Hashem Is Father to the Fatherless
Children & shidduchim
The Vilna Gaon taught that the midrash on the verse "I am the First and I am the Last" was misprinted, and that its true wording is: I am the First to those who have no father, and I am the Last to those who have no sons. Hashem is therefore the Companion of the convert who has left his father's house behind and has no children to accompany him in the World to Come.
Source: The Vilna Gaon, on Yishayah 44:6 (as quoted to the Ger Tzedek)