Stephan II, Graf von Sponheim - Wife and Mother

I just noticed that this Stephen and hsi father have wives with exactly the same names, which could happen but is unusual. So I was reading the profile notes for this Stephen and it doesn't mention his mother, only his wife with the name Sophia Hamm. So next I went to the Wikipedia link in the profile notes and it's clear this Stephen's mother is unknown and didn't have the same name as his wife:

Stephan I. († ca. 1080), (certainly a cousin of Siegfried I. ), Count of Sponheim ( [1] , [2] ), ⚭ NN, possibly sister of Count Berthold IV. von Stromberg ( Berthold-Bezelin )
A: Stephen II († ca. 1118), Count of Sponheim, ⚭ Sophia, probably Sophia of Formbach , German anti-queen ( [3] ), but perhaps Sophia of Hamm , daughter of Count Berthold

In fact, it appears to be uncertain what the maiden name of his wife Sophia was - whether Formbach or 'of Hamm'.