Penny Lancaster is all about family - especially her children and stepchildren. In an interview with the Times of London published on Friday, September 26, Lancaster, 54, revealed she helped husband Rod Stewart's daughter Kimberly Stewart when she wasn't producing enough milk to breastfeed following the birth of her daughter, Delilah, in the summer of 2011. "It was a real motherhood bonding moment," Lancaster told the outlet. "The breastfeeding nurse said, 'In a perfect world, you'd know someone who's breastfeeding' - and everyone turned to look at me." Lancaster gave birth to her and husband Rod's second son, Aiden Stewart, in February 2011. Rod Stewart's Daughter Kimberly Stewart, 45, Reveals Is Pregnant She continued: "I remember thinking, 'What's the most important thing for this child?' I knew my milk would give her the nutrients and antibodies she needed." Lancaster, who is promoting her memoir Someone Like Me, has two sons with Rod: in addition to Aiden, now 14, the pair share Alastair, 19. She's also a stepmom to Rod's six children from four previous relationships: Sarah, 61, Kimberly, 45, Sean, 44, Ruby, 37, Renee, 32, and Liam, 30. Rod shares Kimberly and Sean with his ex-wife Alana Stewart, Ruby with ex-girlfriend Kelly Emberg and Renee and Liam with his ex-wife Rachel Hunter. He shares Sarah with ex-girlfriend Susannah Boffey. In her book, Lancaster reveals Stewart didn't want children when they first met. "I don't want to get married and I don't want any more babies," she explained, adding that "it became an unspoken understanding that if we weren't headed in the same direction, I would want to move on." Rod Stewart and Penny Lancaster Jeff Spicer/Getty Images for Paramount Pictures But the "Maggie May" singer changed his mind in 2004. "Suddenly, Rod turned to me and went, 'Let's make a baby.' I was like, 'Oh my God, oh my God, oh my God!' It's all I wanted," she explained. The pair first met in 1999, after Lancaster had the opportunity to photograph Rod at a concert. "When we first met, I got her phone number - I had just broken up," Rod told Loose Women in a 2015 interview. "I gave it to the bass player ... and he kept it for six months!" The pair went on their first date in August 1999 and got engaged years later in March 2005. Their first son was born in November of the same year. Benicio Del Toro, Kimberly Stewart's Daughter Is All Grown Up in Rare Photo Lancaster and Rod renewed their wedding vows in 2017. "Penny is my whole world. What a girl," Stewart told Hello! Magazine at the time. "Love means many things to many people but to me it's wanting to share everything with the one you love and I love Penny more now than ever, if that is at all possible. It was a beautifully romantic thing to do. We're not proving anything, just sharing our love with our friends and family."