And according to the star, Maxi is even more of a fashionista than she is.
“She teaches me a lot about outfits, and she is better at putting outfits together than me,” Simpson, 36, tells PEOPLE in the latest issue, out now. “She’s a new inspiration.”
The star adds that she has a “warehouse” full of clothes she’s saving for her daughter to wear one day, even though they may not fit her.
“Maxwell is probably going to be taller than me in a year,” she shares. “She’s only 4 and she’s gonna be taller than me.”
Included in Simpson’s “warehouse” are hundreds of shoes, plus prom dresses, music video ensembles and beyond.
“I’m a vintage buyer so I collect. I have all my prom dresses. All my music video outfits. I went to a lot of proms. That’s why we have a warehouse. I’m a keeper for my daughter,” she says. “All I want to do is keep everything. And everybody is like, ‘Throw it out, throw it out.’ But I’m like, ‘No, it’s so important — this is the moment one guy gave me a rose…’ I have a lot of memories. I keep memories. The clothes are memories.”
Simpson says her goal with her accessible fashion line is to make all women feel confident, a message which she’s passing on to her daughter.
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“I feel like it’s important as a woman to know that you can make someone else feel good in her own shoes, make somebody else feel good in her own clothing,” Simpson says. “As a mother, I know how much my daughter respects a great outfit.”
For more from Jessica Simpson, pick up the latest issue of PEOPLE, on newsstands now.