The twins' mother in Sofia the First, Lorelei, tragically passed away due to severe complications shortly after giving birth to Princess Amber and Prince James.
The Fate of Lorelei
Lorelei's death occurred after a wish came true, leading to the birth of her twins: Amber, followed seven minutes later by James. However, her physical health was critically unstable, and she was unable to withstand the complications arising from childbirth. She fell gravely ill and subsequently died, leaving King Roland heartbroken and the young children without their mother.
This unfortunate event shaped the early lives of Amber and James, and it is why King Roland later marries Miranda, Sofia's mother, bringing Sofia into the royal family.