LOS ANGELES: Grammy-winning singer-songwriter Miley Cyrus was totally unaware of the alleged "drama" unfolding in her family.

A source said: "Miley had no idea about the drama with Dominic. No idea at all," reports 'People' magazine.

Earlier, it was reported widely in the media that her sister Noah Cyrus and Dominic Purcell were dating each other before his marriage to their mother Tish Cyrus, 56.

The insider further mentioned, quoted by 'People', "She confronted her mom about it. She thinks it’s a strange situation, but she loves her mom and wants her to be happy."

Earlier, this week, a source told 'People' that the younger Cyrus sister was upset over her mom's relationship with the 'Prison Break' star.

The insider claimed that Noah and Purcell had previously hooked up but they stopped seeing each other before the actor and Tish had pursued their own relationship.

"Noah and Dominic were seeing each other in a 'friends with benefits way', off and on. They stopped seeing each other and then Tish started something up," the source said, adding that "Tish knew he had been seeing Noah".