Katharine McPhee's Sister, Adriana, Files For Divorce After 11 Years Of Marriage

Katharine McPhee's sister Adriana McPhee Collin is filing for divorce from her longtime husband, Edouard Collin.

The "American Idol" alum's older sister filed the lawsuit on July 20, asking that their union be dissolved.

In exclusive documents obtained by The Blast, Adriana submitted the divorce papers at the Stanley Mosk Courthouse, asking to end her marriage of 11 years and 1 month to Edouard.

The estranged couple became legally married on June 30, 2011, and their date of separation is listed as January 8, 2022, meaning they haven't lived together as husband and wife for more than six months.

Adriana and Edouard share two minor children, William Robert, 5, and Georges Daniel, 2. Both parties are seeking joint legal and physical custody of their sons. Details of child support haven't been disclosed yet.

The known vocal coach is divorcing her husband on grounds of irreconcilable differences and is asking to terminate the court's ability to award spousal support to Edouard.

Edouard also wants the same thing, asking to terminate the court's ability to award spousal support to Adriana. The lawsuit states that as regards separate property, "All such assets and debts if any, as are ascertained and discovered according to proof at the time of trial, or as disposed of pursuant to a written stipulation of the parties."

Adriana gave the courts permission to determine rights to community and quasi-community assets and debts as follows, "All such assets and debts, if any, as are ascertained and discovered according to proof at trial, or as disposed of pursuant to a written stipulation of the parties."

It hasn't been determined if either party would be responsible for paying attorney's fees and costs.

The lawsuit to end her marriage comes a day after Adriana, the co-owner of McPhee Int'l Vocal Studios, turned 40 and enjoyed a lavish celebration hosted by her beloved sister Katharine.

The respected vocal coach who works with "American Idol" and Fox's "I Can See Your Voice" took to her Instagram story to detail the outdoor celebration which showed her spending time with Katharine and their mother, Peisha McPhee.

"My stunningly gorgeous and so dam generous sister threw me the best 40th bday weekend any lady could hope for," Adriana wrote in her Instagram Story update.

She continued, "she asked me not to thank her anymore so this is the last time. Seriously, sissy thank youuuuuu! For the last time today!"

The "Country Comfort" star's husband, David Foster wasn't absent from the family celebration as Adriana lauded him for "playing some interesting tunes."

While Adriana was putting an end to her marriage, her sister Katharine's marriage to Foster seems to be thriving. The lovebirds recently raised the temperature on the Instagram timeline with steamy loved-up pictures.

Katharine posted pictures of her smushing the Canadian composer outdoors, at Adriana's birthday celebration. The "Smash" star locked lips passionately on her husband's lips as she wrapped her toned legs around his waist. She held onto him tightly with one arm around his neck and the other caressing his face.

The "Best Of Me" singer couldn't seem to get enough of his wife as he lovingly placed his hand on her bottom. Katharine seductively teased fans, almost revealing her underpants with her grey skirt slightly raised.

She hilariously captioned the post, "poor guy...too bad he doesn't get very much attention." Fans couldn't help but shower the couple with praises and affection in the comments section.