Pregnant Kate Hudson flaunts her bare baby bump during workout with cute little niece

The 39-year-old actress and author, Kate Hudson, is in her second trimester and shared photos of her belly via the Stories feature on Instagram.

Unfortunately, images shared to Stories only stay online for 24 hours, but Pop Culture saved screengrabs of the images before it disappeared.

Hudson is determined to remain fit throughout her pregnancy and found the perfect workout partner in her 4-year-old niece, Rio Laura, who is affectionately known as Riri.

Rio is Hudson's brother's youngest child and loves to spend time with her famous aunt. Her father, Oliver Hudson, said Kate "loves my daughter and is with my daughter all the time."

In April, Hudson shared a video clip of Oliver, and wrote in the caption: 'This is my brother.' She tagged his account, @Theoliverhudson, and used the hashtag 'splitting up together tonight.'

In the last slide, Hudson can be seen smiling for the camera while holding her belly. The text 'happy belly' was superimposed over the image, and Hudson was wearing a sports bra and leggings.

Hudson announced the pregnancy on Instagram in April this year by sharing a short clip of her gender reveal party. She was absent from social media because she had 'never been more sick.'

This is Hudson's first child with boyfriend Danny Fujikawa, but Hudson also has two sons from previous relationships.

The Almost Famous actress was married to Chris Robinson from 2000 until 2006. They have a son together, Ryder Russel Robinson, who was born in 2004.

Hudson also dated musician Matt Bellamy from 2011 until 2014. They are successfully co-parenting their seven-year-old son, Bingham Hawn Bellamy. They have remained friends despite the breakup.

Fans of Hudson can look forward to her upcoming film, Sister. It is in post-production at the moment and will only be released later this year.