Justin Timberlake and Jessica Biel are ''already talking'' about having another baby.

The celebrity couple, who have five-month-old son Silas, are completely smitten with their little boy and hope to give him a sibling sooner rather than later.

A source close to the famous duo, who tied the knot in Italy in October 2012, said: ''They're already thinking about having more kids.''

The 'Not A Bad Thing' hitmaker, 34, loves spending as much time as possible at home with his son.

The source told Us Weekly magazine: ''They are homebodies. Justin is so happy. He's had career success, and now he says family is the most important thing.''

'Total Recall' star Jessica, 33, is also relishing her new role as a mother and has been ''ordering a lot of organic food and cooking healthy meals'' for her family.

Her former 'Seventh Heaven' co-star and best friend Beverly Mitchell added: ''Jessica's a natural, amazing and perfect mom. But there was never any doubt.''

Meanwhile, the brunette beauty is currently gearing up to launch her new child-friendly restaurant Au Fudge in Los Angeles in the near future.