"She is very happy for Bella," a source close to Kidman tells PEOPLE of her daughter's surprise marriage to British I.T. consultant Max Parker.
"She, like all mothers, wants her child to be happy, and it surely seems Bella is very happy," the source adds.
Cruise himself has been supportive of Bella's marriage, and even paid for the wedding and party.
Bella has been a source of joy for Cruise and Kidman ever since she came into their lives in 1993.
"I got married really fast and really young," Kidman, who was 22 when she met Cruise, told WHO in 2012. "But I don't regret that because it got me Bella and Connor and I did have a fantastic marriage for a long period."
After their initial attempts at having children ended in heartbreak, the couple decided on adoption.
"From the minute Tom and I were married, I wanted to have babies," the actress told Vanity Fair in 2007. "And we lost a baby early on, so that was really very traumatic. And that's when we would adopt [our daughter] Bella."
Speaking on their decision to adopt, and their struggles with fertility, Kidman told PEOPLE, "Children are children – you'll die for your children. And when you feel that as a parent – that's the unconditional love."
After the couple divorced in 2001, Isabella grew up with her father in Beverly Hills and was raised in the Church of Scientology, of which she and her brother Connor are still practicing members.
When asked about her thoughts on her children's religious beliefs, Kidman told The Hollywood Reporter in 2013, "I've chosen not to speak publicly about Scientology. I have two children [adopted with Cruise] who are Scientologists – Connor and Isabella – and I utterly respect their beliefs."
Despite living away from her adopted children, and having two more kids, Sunday Rose and Faith Margaret, with her current husband Keith Urban, Kidman continued to have a presence in both Bella and Connor's lives. "I have four children, so to stay in touch with them is very important," she told DuJour.
Always close with her father, Isabella embraced life with her stepmom, Katie Holmes, when she and Cruise married in 2006. Isabella even worked at Holmes' clothing line, Holmes and Yang, for a time.
When Cruise and Holmes had their baby girl, Suri, later that year, Cruise made sure his children from both marriages grew up as family.
"I'm so happy with three [kids]," Cruise told PEOPLE in 2012. "I'm enjoying every second with Suri that I have. And I'm enjoying the relationship with my older kids, and the way it is right now."
In Christmas of 2012, the actor gushed to reporters that he was looking forward to spending his time off with all three of his children. "We have got lots of very special things planned [for the holidays]," he said in London while filming Edge of Tomorrow. "We are all going to be together. I am looking forward to it." Cruise and Holmes divorced in 2012.
Over the past three years, Isabella has been working toward a career as a professional makeup artist, and recently graduated from West London's Delmar Academy of Make-up and Hair.
"All of my kids, each one will do what they're going to do," Cruise told PEOPLE in 2013, "and I'll support them in whatever it is they want."
Kidman echoed a similar sentiment in 2014, telling Australia's The Weekly magazine, "They are generous, kind and hardworking. And these are traits that I love to see in my children."