Your child was likely given Harpy as a race since it is later on the list of races checked for 50+ genetics. The latter race checked for is always the one chosen, and the order appears arbitrary. This issue would exist with a 50-50 child, so 100+ genetics is not relevant.
There was an issue with the code to change 100+ genetics to 100 in v0.9.5, so if you got someone pregnant in that version then it would persist even in v0.9.6. If not, then I'm not sure of the cause of the 100+ genetics, since I've read the related code multiple times and not seen anything wrong.