The actress, who also portrayed British royal Kate Middleton in TV movie William & Kate, announced the happy news on Instagram on Wednesday (26Oct16), together with a picture of a Halloween pumpkin.

The 32-year-old wrote: "We are beyond happy and i cannot wait to bring you all on this journey with me!!!! I'll be posting progress pics as the weeks go on but for now i figured id (sic) post this pumpkin because come spring ill have a belly that size..."

She added, "I am SO excited to FINALLY share with you all news that ive (sic) managed to keep secret for what seems like forever now... This girl gets to be a 'cool mom' ha!"

The child's father is actor Matthew Alan.