Right & Left handed ! Fun fact: the girls are mirror reverse identical twins. 🧬 What “mirror image” means Mirror twins develop from a single fertilized egg that splits a bit later than usual—around 7 to 12 days after conception. Because the split happens after the embryo has started organizing left–right features, the twins often have opposite physical traits, such as: • One is right-handed and the other is left-handed • Birthmarks or hair whorls appear on opposite sides • Teeth may come in on