Kristen Stewart's 'Momentary Discretion' Lasted for Months, According to Rupert Sander's Bro in Law

What Kristen Stewart referred to as a "momentary discretion" could be much longer affair than just a one time passionate kiss caught on photos.  Rupert Sanders' wife Liberty Ross' brother said that the secret relationship went on for months.

Photos of Stewart and Sanders appearing cozy were taken as far back as May 15 at a restaurant in Berlin.

Ross' brother Leopold said to People.co.uk, "It was from the last half of filming and all through post-production, clear into last week."

Leopold shared that his sister had sacrificed so much in order for Sanders to be able to pursue his Hollywood career.  She left behind her successful modeling career to look after their two young children.

Leopold also said, "She made some sacrifices for something she thought was worth it, now she knows, right? Five minutes from her home."

Ross met Sanders when she was just a teenager and they have been married for 10 years.  

After Sanders' infidelity was surfaced through photos captured by a photographer, he issued an apology towards his family.

"My beautiful wife and heavenly children are all I have in this world."

"I love them with all my heart. I am praying that we can get through this together."

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