A case playing out in South Florida is a cautionary tale about how personal rifts might affect business.

It stems from a family dispute that has given rise to a $6 million spat and breach-of-contract litigation involving the president and the vice president of a Miami Beach hotel.

Plaintiff Diego Agnelli has served as the president of Lennox Miami Corp. for the last decade. Agnelli has accused his father-in-law, Juan Castellanos Bonillo, vice-president of Lennox, of firing him without cause.

The complaint was filed Wednesday by Agnelli's lawyer, Jesús E. Cuza, who is a partner at Holland & Knight in Miami. It alleged that the end of the marriage between Agnelli and Castellanos' daughter led to an unlawful firing.

Now, Agnelli claims he's fighting back, asking the U.S. District Court for the Southern District of Florida to order Castellanos to pay money allegedly owed under an employment agreement.

Read the full complaint:

Lennox's employment agreement had a termination-without-cause provision, according to the complaint.

"If the company terminates this agreement without cause, the parties acknowledge that the actual damages likely to result from breach of this agreement are difficult to estimate on the date of this agreement, and would be difficult for the parties to prove," the pleading quotes the provision as stating. "Accordingly, the parties agree that in the event of any breach of the obligations and responsibilities set forth in this Section 2(b), the company shall pay the employee USD $6 million, which amount reflects five years of employee's salary, as liquidated damages."

Luis Salazar, a partner at Salazar Law in Fort Lauderdale representing Lennox, and Cuza declined to comment.

The Lennox hotel is a landmark on Collins Avenue in Miami Beach. It is a modern reinterpretation of an iconic 1930s Art Deco revival building.

While Agnelli was president, he had a role in the day-to-day operations of the Miami Beach hotel, including cultivating the image of its brand, while Castellanos provided investment capital for Lennox.

At Lennox, Agnelli had several roles, focusing on the big-picture development, construction, design, marketing and sales. To that end, court pleadings claim Agnelli secured lucrative high-end events at the hotel involving companies like Paraiso, which held its Paraiso Miami Beach Swim Week show at Lennox because of Agnelli's involvement with the Miami fashion industry. The complaint also touted Agnelli's aggressive sales approach, which it claims led to a significant increase to the bottom line, with a high-end buyout group for the 2020 Super Bowl in Miami, which allegedly generated $500,000 in revenue over four days.

The complaint alleges that despite the success, when the marriage ended between Agnelli and his wife, so did the relationship between him and his father-in-law.

Agnelli accused Castellanos in the complaint of locking him out of the hotel when he returned from an out-of-state vacation with his kids, not allowing Agnelli to retrieve his personal property and seizing control of the premises.

Then, Agnelli stated in the complaint, to "punish, harass and bully" his former son-in-law, Castellanos caused Lennox to "unlawfully and constructively terminate Agnelli without cause."