Ashlee Simpson on being a mom to two and how sister Jessica is as an aunt

BY: GIBSON JOHNS

Ashlee Simpson and Evan Ross -- her husband of just over a year -- welcomed their first child together, Jagger Snow Ross, at the end of July. And it's been an amazing first three months with their daughter.

When speaking with Simpson and Ross, it becomes abundantly clear how adoring they are as parents to Jagger ... she was even holding her during our interview! One of Simpson's favorite parts of having a baby girl? The clothes, of course.

"It has been so much fun dressing her. We change her outfits all the time -- having little girls' clothes now is so fun," she says. "Her room is also really cute -- I don't think she realizes how cute it is yet. She definitely has a little bohemian room; it's super cute."

Though a lot of the focus has been on Jagger in the few months since her birth, Simpson spent just as much time discussing her 6-year-old son, Bronx, who she had with her ex-husband Pete Wentz.

Photos from Simpson and Ross' first appearance since Jagger's birth:

"He's awesome, and he's such a good brother. He's like a professional big brother, and he's got it down: He can calm her down and tell her it's ok, entertain her, and dance with her. He's a really good big brother."

Since giving birth to Jagger, Simpson has put all of her focus on being a mother. So when she and Ross made their first public appearance at the Guitar Hero Live launch party, it was a welcome night out.

"It was so much fun -- Evan and I had such a blast!"

Before heading out to the Guitar Hero Live event, Simpson and Ross said that Bronx was super jealous that they got to go out and play a video game. After all, he plans on being a video game for Halloween!

"We were showing Bronx what we were doing, and he was like, 'I want it! I want to play!,'" Simpson details. "He totally wants to be a rockstar -- he already is a rockstar!"

When comparing raising Bronx versus raising Jagger, Simpson hadn't really seemed to have given the idea much thought yet.

"It's been such a long time [since I raised Bronx]," she muses. "So maybe my age makes it a little different and, now having Bronx around, I have kind of a team. It's nice."

She continues, "In general, your second child is way more laid back. I was pretty laid back with Bronx, but this time you definitely know what you're getting into it. There's an ease with that."

Regardless of any differences this time around, the singer has definitely kept one thing constant: Love.

"The key, for me, is letting them know that they're loved."

Letting her two adorable children know that they're loved must not be too difficult for the parents, considering how big and supportive their extended family has proven to be. Most notably? Simpson's sister, Jessica, and Ross' mother, Diana.

"[Jessica has] always has been a great aunt ... both with Bronx, and now with Jagger."

Though everyone in their clan is busy with their own packed schedules, the pair is looking forward to Thanksgiving and spending time with everyone under one roof, a moment that will be a first of many in Jagger's near future.

"We're so lucky! We're a very close family. Next we have Thanksgiving -- Jagger's first one! We'll be with the family then."

More photos of Simpson and Ross together:

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