[LD] Grimborn Birth Marks Customization

I finally had babies with Grim (twins to be precise). I saved the family and aged the kiddos up, really to see what they would look like. What I noticed is that the birthmark appears as a skin detail for the body, but does not appear as an option. I understand why it doesn't as it's something specific to being Grim's kid. On the other hand, it sucks that it's not available to atleast change the color as the birthmark on Grim's daughter changes to the red swatch instead of staying as the brown swatch. It's not the worst, but her twin brother's stays the same throughout the aging up. I just wish there was a way to change it to keep it consistent, if that is what you want, or keep it as is. You can manipulate it a bit by changing their skintone to a different swatch and then switch it back. I still wish there was a way to change it's color though.

I haven't a clue if it's a bug or by design, so that's why I posted here.