Jennifer Aniston's Mayer baby

Jennifer Aniston is reportedly pregnant with John Mayer's baby.The former 'Friends' actress, who recently rekindled her relationship with the 'Gravity' singer, is believed to have decided to give their romance another try after discovering she was expecting her first child, according to Australia's New Weekly magazine.A source said: "Jennifer is over the moon. She doesn't want to be a single mom, so she is willing to give John the chance to prove his parent potential."The couple have been seen out on several dates recently, while Jennifer's figure is said to be looking a little more rounded than usual.It was recently revealed John penned Jennifer a love song and promised to cut out his unhealthy vices to cement their romance.A source said: "John has written a song about their time together and played it to Jennifer who was incredibly touched."He has cut right back on his drinking and has pledged to quit smoking roll-up cigarettes - two things that really annoyed Jennifer."

The couple sparked speculation they had reunited after they were seen passionately kissing at a Ray LaMontagne concert before sharing a private plane to Los Angeles.

John was also seen "sneaking out" of Jennifer's home last week, while the 39-year-old actress helped her 31-year-old lover celebrate his birthday later in the week.