Jo and Sienna MillerJo and Sienna MillerSienna Miller's got a fighter in her corner.

Her mother, Jo, has had a word on Si and Balthazar Getty's relationship.

What's her beef?

According to IMDB, Jo said: "You can't understand how a woman seeing a man who has been separated from his wife for months can cause such a scandal.

"It's awful, I can't tell you. You wonder when it's all going to stop."

Jo also went on to say: "Thank goodness some people are seeing the hypocrisy of it all.

"I know it makes Sienna pleased to read these things.

"It means a lot to her when there's so much negativity and criticism around."

Good ol' mums, they'll never let you down.