Jennifer Aniston and Justin Theroux

Jennifer Aniston and Justin Theroux

Jennifer Aniston and Justin Theroux are waiting for the right time to have a baby.

The 45-year-old actress and the 42-year-old actor, who got engaged in 2012, are reportedly very open to starting a family together in the future.

A source dismissed new rumours that the former 'Friends' star is almost four months pregnant with a baby girl, but said: "I know that they would like to have a family if the time was right. At the moment they have been enjoying the engagement."

Justin's best friend, tattoo artist Scott Campbell and his actress wife, Lake Bell, recently announced they are expecting their first child, and the 'Wanderlust' star is planning to offer to babysit.

He said: "Of course I will [babysit]! If they ask me to... but I don't know if they trust me."

He jokingly added: "I might drop it on its head."

Last year, Jennifer indicated that she didn't have an overwhelming desire to experience motherhood.

She said: "I surround myself with my amazing work, my amazing friends, my amazing partner, my beautiful dogs, and I tune that noise out. I mean, I think it's very sweet that people want everything for me, (but) I'm so content and happy."