Keith Urban and Nicole Kidman are a great couple, and if you haven't seen Keith put on a concert...I suggest you get tickets.  But beside that: they might be having another baby in the "near future"

Keith Urban and Nicole Kidman have always stressed family above all else, making professional commitments just as long as they aren’t away from their 2-year-old daughter, Sunday Rose, for long periods of time.

(via Keith Urban and Nicole Kidman Hoping for Another Child - Taste of Country.)