Abraham Friedrich Krohn (1766-1827) and Elisabeth Balser (1770-1837) had seven sons:

1. Andreas Johann (b. 20.10.1794, d. Vienna 1834). Was under 18 when fought in Kutuzoff's troops against Napoleon. Took over commanding an artillery battery In Malo-Jaroslawetz on 12.10.1812, when all older officers were fallen or wounded, and was immediately also himself badly wounded in his right hand. When healed, participated in 1813 in the battles near Leipzig. Unmarried.

2. Alexander (b. 1796, d. 1796).

3. Friedrich Alexander (b. St Petersburg 5.5.1798, d. Dresden 28.8. 1874, buried in the Trinitatis graveyard in Dresden). Director of the family brewery 1819-1858. Worked also in its Moscow branch until 1815. Honorary citizen of St Petersburg 1845. Moved permanently to Dresden in 1858, and in the next year gave up his ownership in the St Petersburg company. Chamber music was often played in his home. The Breitenstein and Madeira Krohn branches start with him and his first wife.

   1st wife 1821 Catharina Biller (b. St Petersburg 17.10.1801, d. 11.4.1849, buried in the family grave in St Petersburg).

   2nd wife 1855 Marie Behling (b. St Petersburg 23.10.1826, d. Meran 27.3.1860, buried in the Trinitatis graveyard in Dresden). She was Orthodox, since her mother was Orthodox. To avoid the obligation to raise children in the Orthodox belief, wedding took place in Viborg, This was possible, since Abraham and his children had Finnish citizenship, to which he was entitled because Rügen was part of Sweden at the time he came to St Petersburg.

   Both wives and seven children died of t.b. Ida was the only one of the fourteen children who was not affected by this disease. The distress caused by t.b. in St Petersburg was the main reason for them to move away from there.

4. Carl Ferdinand (b. 16.4.1801, d. St Petersburg 6.5.1825, buried in the family grave in St Petersburg). Studied medicine in Göttingen together with August. Died of typhoid fever, which he caught in an epidemic in the Obuchow hospital in St Petersburg. Unmarried.

5. August David (b. 11.8.1803, d. Bonn 1891). Studied in Göttingen together with Carl. Lived in Hamburg and Bonn. Specialized in primitive sea life and spent much time in Italy. His careeer ended in blindness. From 1851 on Friedrich's son Alexander took care of his affairs from Dresden. Charles Darwin mentions August in his letters and tells how August had discretely pointed out some grave errors in his work. Unmarried.

6. Leopold Wilhelm (b. St Petersburg 22.10.1806, d. 1890). Worked with Friedrich in their father's brewery. Moved to Finland in 1844. Wife 1834 Juliana (Julie) Dorothea Dannenberg (b. Viborg 3.7.1818, d. Viborg 20.8.1889), daughter from Kiiskilä estate. She was only 16 years and 12 days old when married. The branches of Julius, Leopold and the Hackmans start with Leopold and Julie.

7. Constantin Heinrich (b. St Petersburg 2.6.1808, d. Versailles 16.4.1863). Wife 1850 Josefa Luisa Ramona de la Santa Trinidad de Roa y Morales (b. Cadiz 8.3.1823). Traveled extensively in Western Europe and in the Orient. Without permanent job. Wedding took place in an English church in Gibraltar, since Spanish law didn't allow Protestant to marry Catholic. After marriage settled down in Paris. Had two children, who presumably have no descendants living today.