Daniel Craig and Rachel Weisz's decision to have a child together was a ''natural next step'' in their relationship.

The 'Spectre' star and his 48-year-old spouse - who already has 11-year-old son Henry from her relationship with Darren Aronofsky - have been married for seven years, and last week revealed the happy news that Rachel is pregnant with their first child, which surprised some fans as the pair like to keep details of their relationship private.

But it has now been claimed that those closest to the pair that the decision was a long time coming, and both Daniel - who also already has a child, a 26-year-old daughter named Ella, from his previous marriage to Fiona Loundon - and Rachel had a ''natural desire'' to start a family together.

An insider told People magazine: ''It's not surprising that they want a child together. They are both smart and secure and having a child is a natural next step even though both have children from other relationships.

''They admire each other and want to keep their marriage alive and exciting. She is independent and their marriage is solid. Having a child is a natural desire. They have been married long enough to know each other which is a mature step to be sure nothing goes wrong.''

The 'My Cousin Rachel' star revealed her pregnancy last week, and admitted recently that she had been feeling ''dodgy'' during the first few months.

She said: ''Doing pretty good now. I was feeling very dodgy for about four months, but now the good bit's kicked in.''

The 'Mercy' star announced that the couple have a ''little human'' on the way during an interview with the New York Times newspaper, where she revealed: ''I'll be showing soon. Daniel and I are so happy. We're going to have a little human. We can't wait to meet him or her. It's all such a mystery.''