Megan Fox hopes her son will be ''an amazing big brother with time.''

The 'Teenage Mutant Ninja Turtles' star is set to give birth to her second baby with husband Brian Austin Green soon and admits she isn't sure how her 14-month-old son, Noah, will react as he loves being the centre of attention.

The 27-year-old actress told ''We are trying to explain it to him and I always say, 'The baby is going to say, ''Wah, wah, wah,'' ' because he is not communicating yet [so] I'm not sure how much he understands.''

She added: ''I know as far as everything else goes, he's really aware. So I think he has an idea, but I don't think he understands that a baby will be living with us all of the time - that will be an adjustment.

''He loves to be the centre of attention and I also think he is a really sensitive child. I think that he's going to be a nurturer. It's a lot to expect, but he's only 14-months now. I think he's going to be an amazing big brother with time.''

'Anger Management' star Brian, 40, added: ''He is either going to be great or ... he's going to be completely against it and it will be a battle.''

Megan, who has been enjoying an ''easier'' second pregnancy and is rumoured to be expecting another baby boy, also revealed her sense of smell is very sensitive at the moment.

She explained: ''I can smell everything! I usually can smell foul scents, I pick them up from far away. [Brian's] constantly saying, 'I don't smell that, you are crazy, that's not in the house,' and I'm saying, 'I promise you, it is somewhere.' ''