A day after Paris announced the name of her son, she also shared the first pictures of Phoenix.
"Baby Phoenix. Our whole entire world. 💙" she captioned two photos of herself, Phoenix and Carter.
The heiress explained the meaning behind the name in her podcast This Is Paris, telling listeners, "this is a name that is so special to me."
"I've been planning my children's names for years and years," she shared, before noting that it was "hard to think of a boys name."
"Over a decade ago I thought of this amazing name," she shared. "It's such a beautiful name, it's so unique. I love that it is not only a city but it also has other meanings that are just beautiful. I really believe that names have power and we wanted a name for our baby boy that was uniquely remarkable."
Paris shocked fans in January on Instagram when announcing the birth of her son.
On January 24, the heiress posted a picture of her and her child's hand, writing "you are already loved beyond words."
PEOPLE confirmed the couple, who previously began an IVF process during the height of the COVID-19 pandemic, introduced their son, via surrogate.
"It's always been my dream to be a mother and I'm so happy that Carter and I found each other," the new mom told PEOPLE exclusively. "We are so excited to start our family together and our hearts are exploding with love for our baby boy."
Paris shared more details on why she chose to keep the news to herself during an interview with Harper's Bazaar.
"My entire life has been so public," she explained. "I've never had anything for myself. We decided that we wanted to have this whole experience to ourselves."
Paris, 41 and Carter, 41, got engaged on Paris's 40th birthday. She revealed on Instagram that her partner businessman Carter Reum, popped the question on their private island holiday where they were celebrating the business mogul's birthday.
The loved-up couple has been together since their first date in 2019, but they have actually known each other for over 15 years.