Did Miranda Lambert Spy On Blake Shelton Before Their Divorce?

Miranda Lambert was so suspicious of then-husband Blake Shelton that she spied on him, according to new reports.

On Monday, the couple revealed they filed for divorce after four years of marriage.

Now reports have suggested that Miranda, who is the daughter of two private investigators, began sleuthing before their split.

Read: Blake Shelton Reportedly Upset by Rumors Miranda Lambert Cheated on Him

"She had spies everywhere," a source told US magazine. "He was never left alone. She was jealous and so controlling of him."

Miranda reportedly spent a lot of time on the set of The Voice in Los Angeles so that she could keep close tabs on her husband.

Following the divorce announcement, rumors have swirled over whether either party was unfaithful.

According to reports, Blake was upset because of rumors his wife cheated on him with singer Chris Young, her one-time her opening act. Young denies there was ever any affair.

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A source close to Blake insisted to People magazine that the musician had been loyal to his wife.

"Blake is just that incredibly loyal and dedicated husband," the source said. "I can guarantee you he has been faithful to that woman. He hasn't cheated ever."

Watch Below: Did Miranda Lambert Cheat on Blake Shelton?