In the looks department, Jessica Simpson's brand-new little boy, well, aced it! "The baby is beautiful," a pal tells Us Weekly of Ace Knute Johnson, whom Simpson delivered via C-section in L.A. Sunday June 30. And he takes after his handsome father, Simpson's fiance Eric Johnson, the insider adds: "He has Eric's little chin dimple!"

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Engaged since fall 2010, the Fashion Star mentor, 32, and the former NFL pro, 33, "are so happy to have a boy," notes the source. "One of each, everybody wants that!" With a middle name that honors his Swedish grandfather, Ace Knute (pronounced Ka-nute) joins big sister Maxwell Drew, 14 months.

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"Maxwell is excited," the source tells Us of the blonde, blue-eyed toddler. "She doesn't totally get it and understand, but she is very excited to have a brother.

Since Ace's Sunday arrival, the second-time parents have received visits at the hospital from Simpson's parents Joe and Tina, sister Ashlee -- and Simpson's still-pregnant BFF Cacee Cobb.

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Expecting her first child with husband Donald Faison, Cobb, 35, sounds like she's smitten with her honorary new nephew. "IN LOVE," she tweeted Sunday in a message surrounded by hearts. Added proud grandfather Joe Simpson:"Very blessed to celebrate the birth of my new grandson."

Jessica, meanwhile, "is ecstatic," the source notes.

This article originally appeared on Jessica Simpson's Baby Son Ace Knute Johnson Is "Beautiful"