Not to be this person, but I’m going to be so I guess 
:
One, full cc with a mc and taking parents/ siblings/grandparents into account is hard. I’ve been trying to get it figured out for my contest entry and it’s hard enough getting skin tones to match, nose shapes that look like they go together, figuring out lip colors that match the corresponding skin tones for the male in the family…It’s already a lot without worrying about specific genes. I don’t care if the mom looks like she could be the mcs sister, at least they look related and don’t look like the mc was adopted. 
Now, if it’s a non-customizable character that’s a different story. However, episode is an app for entertainment, not really scientific accuracy.