Miley obviously didn't consider the 'mother-in-law' when organising the penis rodeo for her 22nd birthday. As for the oversized hash leaves and the topless part of the proceedings, well, they left a lot to be desired too.

Maria Shriver is reportedly 'very worried' that how her son with Arnold Schwarzenegger is being influenced by his new girlfriend after seeing pictures of the birthday shenanigans.

A source explained: "The birthday party with all the penis pictures disgusted her. That was the worst thing Miley could have done. Maria is very, very worried about the influence Miley's having on Patrick. She fully believes that you become who you surround yourself with and she's always been so happy with the friends Patrick chooses, she never saw this coming."

A slightly unfortunate turn of phrase there.

Despite Maria's dislike for Miley, she may struggle to separate her son and the We Can't Stop hitmaker after a source revealed that the singer has always been his "celebrity crush."  That's gas, you never would've guessed that looking at this...

The source told HollywoodLife.com: "Miley has been his celebrity crush forever, so he is now living a dream come true. She is so cool and he loves hanging out with her. They have so much fun together."

Meanwhile, another random source added: "He is definitely falling hard for her and she really is liking all the attention he is giving her. This is something that is going to last... It could definitely lead that way and if Patrick gets what he wants it will, but they don't say 'I love you' to each other yet. Way too early!"

Yeah, it's not like she's ready to get engaged or anything!