Nicole Richie is open to having more children.

The 'Candidly Nicole' star, who has daughter Harlow, six, and son Sparrow, four, with husband Joel Madden, admits both pregnancies came as a surprise and they plan to continue to ''go-with-the-flow.''

Asked if she and 'Good Charlotte' rocker Joel, 35, would like another baby, the 32-year-old star told 'On Air with Ryan Seacrest' on KIIS-FM radio: ''We didn't plan the first two, so it's not really up to us, I guess. We're just a go-with-the-flow ... we've never done anything in traditional order.''

The reality TV star considers herself a ''fun'' mother and dyed her hair blue for Harlow.

She said: ''My daughter picks out my hair colours and she's having fun with it and it makes her happy, so I just thought, 'Why not? It's temporary.' She likes it. And anything that makes her happy, makes me happy. It's summer.''

Earlier this year, the fashion designer admitted she still struggles to balance motherhood and her career.

She said: ''Motherhood makes you way more conscious of how you distribute your spare time. Kids are so precious that your priorities change completely. I think that's a global struggle and we, all women, are constantly trying to find a solution.''

She added: ''I'm like any other working mother trying to make things work and dealing with this situation one day at a time. I have an amazing family and they've all been very supportive, my parents live only 10 minutes away and my husband and his twin brother help me when I need it.''