Welcomed their first child a son, Andrea Nicolás Vallejo-Nágera, born November 14 2010 in a hospital in Miami, Florida.
On 30 April 2007, she married Spanish public relations executive Nicolás "Colate" Vallejo Nájera in Xcaret, a park on the Mayan Riviera in Cancún, Quintana Roo.
On 5 May 2010, Paulina announced through Twitter that she is expecting her first child. Her brother, Enrique Rubio, has corrected the statement that she is supposedly expecting twins, which is not true. Paulina has stated that if the child is a boy, he shall be named after his father, Nicolás. If it is a girl, she will be named after Rubio's great-grandmother, Micaela. On 15 September 2010 Paulina announced on her Twitter page that she is expecting a boy. On Sunday, 14 November 2010, Paulina and her husband Nicolás Vallejo-Nájera welcomed their first child, a baby boy named Andrea Nicolás Vallejo-Nájera Rubio in Miami, Florida. Prior to the birth Paulina had planned on having a water birth at home, but was rushed to the hospital and spent the weekend with doctors working to stabilize the health of the baby. Hospital staff tried to send Rubio home so that she could realize her dream of a natural home birth, but the complications lead her medical team to schedule a c-section.
In March 2012, Paulina's husband, Colate, told Hola! that he and Paulina are separating after nearly five years of marriage. "It has been a decision by both of us, though it’s possible that I have been more firm when it came to carrying it out," he said in an interview with the Spanish publication."I have the feeling there is no going back," Vallejo-Nagera said, disclosing that he and Rubio have been living apart since November and that their only communication with each other is about their son, Andrea Nicolas, born in November 2010. Colate said that while he will always be "grateful to Paulina" for their time together, his devotion to the marriage caused his business interests to suffer. "I decided to help and support my wife, which has caused me many problems that are costing me very dearly," he said.