Miranda Lambert reportedly closely observes husband Blake Shelton’s flirty ways.

The country singer apparently "keeps an eye on" her musician spouse because she knows his friendly attitude can be misconstrued.

Miranda ensures he stays in line when enjoying conversations with those of the opposite sex.

“[Miranda] knows [Blake] comes off as flirty,” a source told Us Weekly. “She questions him at times and asks about certain girls.”

The 29-year-old married her 36-year-old partner in 2011 and they are regularly the subject of cheating rumours.

The Voice mentor Blake was hitched to high school sweetheart Kaynette Williams when he got together with Miranda.

“The rumours are hard for her to hear,” the insider continued, referring to his alleged philandering ways with 23-year-old singer Cady Groves.

The pair was involved in messages deemed to be “sexy” via Twitter but Blake “swears up and down that nothing happened”.

Miranda and Blake apparently work hard at their relationship and set rules in order to keep things exciting and fresh.

They use online and telephone communication to stay in contact when travelling separately.

A source explained that the couple goes the extra mile “to make it work. They Skype, text and call each other constantly”.

Miranda told press at the Academy of Country Music Awards recently that, “Divorce is not an option”.