Thiemo II, Graf von Formbach - His mother and wife have the same parents

Medlands has the dau of Bruno as the wife of Thiemo II, rather than his father Thiemo I.  GENI has her as wife of both father and son.

https://fmg.ac/Projects/MedLands/BAVARIAN%20NOBILITY.htm#ThiemoIIdi...
THIEMO [II] [Dietmar], son of THIEMO [I] [Dietmar] Graf im Schweinachgau & his wife --- (-killed in battle 28 Aug 1040). 
m ---. The name and origin of Graf Thiemo's wife are unknown. Wegener suggests that she was --- von Braunschweig, daughter of Bruno [I] Graf von Braunschweig & his wife Gisela of Swabia,

I would suggest following MedLands. Delete his mother and make his wife Unknown von Braunschweig daughter of Bruno I.