Paris spent her 15th birthday on Wednesday with her birth mother Debbie Rowe, who signed away all parental rights when she split with the singer, reported Contactmusic.
"The two just hung out. They've gotten really tight," a source said.
Rowe wed the King of Pop in November 1996, three months before the birth of their son Prince, now 16, and Paris was born just over a year later.
The pair divorced in 1999, when Paris was one, and Rowe signed custody over to the singer as part of her 6.5 million pounds deal.