Twin girls are getting a lot of attention for their appearances, and it’s not just because they’re unbelievably cute.
Kalani and Jarani Dean are biracial twins who were born to a Caucasian mother and an African-American father ― and each girl has a different skin tone.
“Their dad couldn’t believe it,” proud mom Whitney Meyer told The Huffington Post Thursday of her boyfriend, Tomas Dean.
The girls, who were born in April, are now 9 months old, but recently made headlines after Meyer shared their photo with the local news station in Quincy, Illinois.
Exactly how this amazing combination happened goes back to their genetic makeup.
The twins are dizygotic or fraternal, meaning they developed from two different eggs and sperm cells. That separation allowed them to inherit their own individual combinations of genes from Mom and Dad.
Kalani received her mother’s light skin and blue eyes, while Jarani received her father’s darker skin and brown eyes.
“It was right away I noticed a difference,” Meyer said of the babies’ skin tone.
“I did ask the nurses if she was albino because she was so white, and lighter than her sister,” she told Inside Edition.
Researchers in Britain have reported that there’s a one in 500 chance that such a combination can occur among fraternal twins born from parents of different races.
Because there are now more interracial couples in the world, Dr. Nancy L. Segal, psychology professor and director of the Twin Studies Center at California State University, suggested to PEOPLE that this phenomena may become more prevalent.
For Meyer and her family, the twins’ skin color is just a cosmetic detail.
“I don’t know [what] their future holds, being opposite, but everyone else loves them. You can’t just love one and not the other,” she said.
That includes her 7-year-old son, Talan, who is Caucasian and has a different father.
Talan, she said, recognizes that his sisters are different from one another in skin tone. He has consequently pointed out that Jarani’s skin matches the darker tone of his late younger brother, Pravyn, who tragically died at the age of 2, as Meyers told PEOPLE.
“He loves the fact his sisters look like both their brothers,” Meyer told HuffPost of her son.