Geri Horner has admitted that being a single mother to daughter Bluebell was "lonely".
The Spice Girl compared the experience to that of raising her son Monty, six, with her husband Christian Horner. The 51-year-old shares Bluebell, 17, with her screenwriter ex Sacha Gervasi, who she split with before the 2005 birth.
In 2015, the star married Formula 1 team principal, Horner, 49, and a few years later they had Monty together.
Speaking to Giovanna Fletcher on her Happy Mum Happy Baby podcast on Tuesday, the singer detailed her "very different set-ups" raising her children.
She said: "I've experienced both and I can tell you that, yeah, I had my mum to help me with Blue, so I'm very grateful. And her granddad is gorgeous so it was a fantastic role model for her.
"He takes her to football, which is amazing and I think you know, they both have their blessings and challenges."
She continued: "Being a single parent, mother, you don't have to answer to anyone, but it's all on you. And that can be quite stressful...
"Broad shoulders are needed and sometimes it's lonely. So I've experienced that. And then, you know, having the blessing of having a lovely husband or partner, which I've experienced. That's amazing.
"So it's not all on you, but then you've got to compromise... we're all different in the way we think things should be done. So learning to be a team has been a challenge for me."
Halliwell has been promoting her new book, which was inspired by the death of her father Laurence from a heart attack in 1993 - one year before she joined Spice Girls.
Speaking on Lorraine last week, she said she'd found herself writing about her own experiences in the new novel, Rosie Frost and the Falcon Queen.
"It was hard," she said. "I was in class. I got pulled out of class and told what had happened to my dad and I found myself writing that in Rosie. Then I realised I had put myself into the book."
