In her sweet family of five

Meet Nico Valentine!

Fashion designer Rebecca Minkoff presents her new baby, born on Saturday, February 10, in the latest issue of PEOPLE, posing in a series of photos taken at her home in Quogue, New York.

During filming, Minkoff accompanied her husband, commercial manager Gavin Bellour, and their children: sons Nico and Luca Shai, 6½, and daughter Bowie Lou, 3½.

“It wasn't quite the messy, emotional jump from one to two,” the new mother of three, 37, tells PEOPLE of adding another child into the mix. “It’s more of a logistical, I wouldn’t say challenge, but a planning challenge.”

“If we want to go somewhere, we have to plan an hour in advance when we have to leave,” Minkoff explains. “There are just more challenges like that.”

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RELATED GALLERY: Inside Rebecca Minkoff's stunning home renovation

The family's recent Hamptons beach house renovation includes a stunning (and practical) addition: Baby Nico's “bright and airy” nursery with a Hudson convertible crib ($398), a Hayden glider ($2,398) and dip-dyed stools ($58 to $68). , black and white striped rug ($398 to $998) and more from Serena & Lily.

“I want my baby to sleep with me for at least the first six months, so it was fun to design a room that is sophisticated and fits our modern bohemian aesthetic, but also has room for a crib rather than what a baby's room works.” “Minkoff tells PEOPLE about the room.

“I think there is a way to design the nursery and there is a way, especially if you share a room with your children, to maintain the aesthetic as an adult and have a more upscale aesthetic for the baby when your situation changes They didn’t compromise on the design aesthetic,” she adds.

RELATED VIDEO: See how adorable Ginger Zee incorporated a weather theme into her son's nursery

Minkoff says she “definitely doesn't try to buy anything new” for her third child, aside from clothes and diapers, but recommends two high-quality items for new parents.

“The two items I recommend are a great convertible crib. The crib I chose is nice because it can be converted as the kids grow,” she says. “And kind of a good rocker for them.”

Minkoff explains, “It doesn't necessarily have to be the fancy, computerized or electronic devices, but a little exercise in the first few months will definitely help them sleep a little longer.”

RELATED: Rebecca Minkoff presents new collection for “A Pea in the Pod”.

Minkoff tells PEOPLE that she is “very happy” with how her older children have adapted to their little brother and that Bowie has “exceeded” the couple's expectations.

“Our son was great. “He has become more mature,” she praises. “Our daughter, we had very low expectations. She surpassed them. We thought she was hurting him or being jealous, but she was really good.”

For more on Rebecca Minkoff's new family of five, pick up the latest issue of PEOPLEon Friday at the kiosk.