Boy do I get tired of hearing that phrase throughout the day. My three-year-old constantly asks where mommy is, and tells me that it's hard to wait for her. I understand, as I miss my wife during the day too, but hearing it 20 times a day does get old.
It's almost as bad as "Are we there yet?" I used to get that every five minutes when we were on a trip! Your child is at the age when questions are beginning to come thick and fast. Good luck!
I never understood what so many men hated to hear that until my wife had left for a two week work trip that took her half way around the world. While she was out enjoying a company paid trip I was at home ripping my hair out.
Three-year-olds tend to be really clingy to their moms. My youngest is also three and it's impossible for my wife to go anywhere without him screaming that he wanted to come along.
After saying, "She's at work," long enough for the child to know it, turn her question into another question. You ask, "Where is Mommy?" Who knows? You may develop excellent communication skills with your child in the process.
That is a great idea to try to turn the questions into another conversation. It could be used as an opportunity to develop the child's imagination as well.
