Miley Cyrus' romance with new girlfriend Stella Maxwell hasn't gone unnoticed by her ex Liam Hemsworth, who is said to be 'aware' of their relationship.

“Nothing surprises him anymore with Miley but he is not heartbroken, he has moved on,” a source tells HollywoodLife.com.

Adding: “But he is aware of the hookup.”

Considering pics of MiCy and Stella kissing in a car park were circulated across the internet earlier this week, we think it would be kind of hard for him not to be aware of their PDA.

While things look to be getting serious pretty quickly, after Stella was introduced to the singer's parents recently.

“Miley brought Stella home to meet her family and they really like her,” a second source explained.

“Her parents are both on board because they see how happy Stella is making her. They’re happy that she’s happy, and that’s all that matters to them.”

Agreed!