Jessica Simpson celebrates fiancé Eric Johnson’s birthday … with baby Maxwell!

This has got to be Eric Johnson's best birthday yet. Jessica Simpson's fiancé marked the big 33 with a very special guest at his party: the couple's 4-month-old daughter Maxwell Drew. Simpson posted a bunch of too-cute photos from the soiree on her website on Wednesday, and it looks like the smiley little girl was having a good time.

"Last year at Daddy's party, Maxwell was in my belly. This year she's in my arms!" she wrote of the black-and-white photo of her and Maxwell posing cheek to cheek. In another, a casually-dressed Johnson cradles his daughter, who is clad in a white sundress (and some pinch-worthy chubby cheeks).

In a new interview with iVillage, the singer-turned-fashion designer, 32, talked about motherhood and how she plans to raise her first born. As far as what her offspring wants to be when she grows up, "I'm going to let Maxwell do what she wants to do," said Simpson. "I'm definitely going to parent her the way my parents parented me . . . [but] when I was young, I was like, 'This is what I want to do,' and they supported me, and I was doing it by the time I was fourteen years old. I think it's important to encourage from a young age that whatever you're passionate about -- go for it!"

Simpson has been spending so much time basking in Maxwell, she hasn't given much thought to her wedding to Johnson. But she's sure of one thing: "I know it's going to be a perfect wedding," she told iVillage. "I mean, I say that, and it could not be … we really haven't planned it. But I see it being definitely a destination thing and everyone celebrating and being able to dress up and having all of my bridesmaids looking beautiful in whatever designer they want to wear."

More Celebrity Features on Yahoo!:

Follow omg! on Twitter