"They truly are a miracle," says mom Whitney Meyer

By Rose Minutaglio
April 24, 2017 03:22 PM

Happy birthday, Kalani and Jarani!

The Quincy, Illinois, rare biologial twin sisters celebrated their first birthday on Sunday at a princess-themed party, organized by mom Whitney Meyer.

“We had clip-on earrings for the little girls and bracelets and necklaces and coloring pages,” Meyer tells PEOPLE. “We also had a princess piñata!”

Meyer even ordered a custom princess marble cake with cake toppers to reflect each sister.

“I wanted the cake to resemble each [of the girls],” explains Meyer. “So the baker put a lighter skin-toned princess cake topper with blue eyes for Kalani and a princess with a darker skin tone to resemble Jarani.”

Meyer says not only did the twins love the cake, but guests thought it was “adorable.”

“Everyone that came was snapping pictures,” she says. “I just really wanted to let people know that there is nothing but love in this family.”

RELATED VIDEO: Mother of Rare Biracial Twins Born in Illinois Speaks Out: ‘We Don’t See Color’

When Meyer first began posting pictures of her daughters on social media, she says she received some negative comments. But in the past few months, it has been “overwhelmingly positive.”

“I’m so happy about that,” she adds. “You get some people who will say some stuff, but mostly everybody loves their uniqueness. I hope I can bring different people together.”

Meyer and her boyfriend, Tomas Dean, also have an 8-year-old son, Talan, who sticks up for his baby sisters.

“We were at the doctor’s office, and the doctor said, ‘Oh, they’re twins? One is darker…’ And [Talan] goes, ‘Well we don’t worry about color in our family!’ ” says Meyer.

Dr. Nancy L. Segal, psychology professor and director of the Twin Studies Center at California State University, says their different skin colors is “extraordinary.”

“We don’t know how often it happens because not all cases come to our attention,” Segal told PEOPLE in January. “I imagine it’s going to happen more frequently now that we have more mixed marriages.”

She adds: “It could be one child inherits certain genes from both parents and the other child inherits sets of genes from the other parent. And that explains the different skin tones. It’s just like how ordinary fraternal twins can look completely different from each other. They just inherit different sets of genes-one child gets the lighter ones, the other’s darker.

“The fact that these twins are biracial makes this a very extraordinary case.”

Jarani and Kalani in a milk bath with rainbow flowers to represent their lost brother

Meyer says her kids have been instrumental in helping her family recover from the death of their 2-year-old son, Pravyn, who died two years ago in a tragic drowning incident in a babysitter’s pool.

“My girls, they make me get up every day and they give me motivation,” she says. “They truly are a miracle.”