updated 03/15/2014 AT 1:50 PM ET
•originally published 03/15/2014 AT 2:00 PM ET
Don’t tell Diana Ross.
“Honestly, we could go and get married right now, wherever,” the 25-year-old tells E! News at SXSW. “We just want to be married. We’re in love.”
Ross popped the question to Simpson, 29, in January after dating for six months but says he knew “really quickly” that she was the one.
“I would have asked her a month after I was with her,” the Wilderness of James star admits.
The couple have a wedding date picked out and even though his mom is going on tour, she’s helping the couple plan their nuptials. “She’s involved in every piece of our wedding [and] engagement party,” he says. “She’s involved in all levels of my life. She’s one of the most incredible mothers ever.”
Once the couple ties the knot, Ross has something else on his agenda – babies.
While Simpson is already a mom to son Bronx, 5, whose dad is her ex-husband Pete Wentz, Ross would like a big family. “It’s up to Ashlee, but I want to have a lot of kids,” he says. “I grew up with 10 siblings.”