IT’S FINALLY time for baby! Since their wedding in January 2009, Fergie and Josh Duhamel have been constantly asked by their fans when they’re going to have a baby together, and they now have an answer. The couple announced on Twitter Feb. 18 that they are expecting their first child together."Josh & Me & BABY makes three!” Fergie, 37, and Duhamel, 40, both tweeted with a picture of them as children. A source told Us Weekly, "They just found out and tweeted it to the world.”The couple, who wed in January 2009, spoke about their desire to start a family during an October 2012 appearance on Oprah’s Next Chapter. Though Duhamel said he hoped to one day have five children, Fergie lowered his expectations. "We negotiated that early on,” the 37-year-old singer said. "Two is our number.”Duhamel, 40, added that because he and Fergie "grew up in very similar ways,” they’re on the same page when it comes to raising a little one."My mother was a teacher. Both of her parents were teachers. We both had to work for what we got. We’re both Catholic,” he explained. "There were a lot of things that were really compatible between us. But at the end of the day, she’s just an amazing girl.”