Ashlee Simpson expecting

May 29, 2008, 10:00 GMT

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Ashlee Simpson and Pete Wentz have confirmed they are expecting their first child.

The couple - who married at Ashlee's parents' Los Angeles house on May 17 - wanted to wait until Ashlee had safely gone past her first trimester, three months, before announcing the happy news.

They wrote on Pete's website friendsorenemies.com: "While many have speculated about this, we wanted to wait until after the first trimester to officially confirm we are expecting our first child.

"This is truly the most joyous time in our lives and we are excited to share the happy news and start our family."

Meanwhile, Ashlee is set to officially change her surname in honour of her new husband.

The 23-year-old singer will be known to family and friends as Ashlee Wentz and professionally as Ashlee Simpson-Wentz.

She said: "I think it's something a woman should do when they're marrying a man. It's a tradition, and I think it's a great tradition."

Fall Out Boy rocker Pete, 28, insists he would never pressurise Ashlee to change her name, but was thrilled with the decision.

He told People magazine: "These decisions with Ashlee and her name are all completely up to Ashlee. I want her to do these kinds of things the way she wants to do them.

"But I was flattered. I was like, 'Upgrade me!' You know what I'm saying? The Wentz family, our Christmas card just got upgraded! It feels insane. It feels unreal."

The couple's baby is expected this autumn.

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