A North Texas man drowned while saving his fiancée's 6-year-old daughter at Lake Ray Roberts on Saturday.

Brandyn Mitchell (via Facebook)

Authorities were called to the Isle du Bois beach around 1:15 p.m. after a man was reported going underwater.

Game Warden Darla Barr told the Denton Record-Chronicle that the man had helped get a child onto a flotation device but was unable to get on it himself. After the child made it to shore, bystanders couldn't find the man.

Just after 4:30 p.m., rescuers with the Lewisville Fire Department's dive team pulled the body of 25-year-old Brandyn Mitchell from water that was about 6 feet deep.

His fiancée, Angelia Herrera, told the Fort Worth Star-Telegram that he had dived into the lake to rescue her 6-year-old daughter, Keira.

"He wanted to be a hero, not just once but every chance he could," she told the newspaper. "Shortly put, he was an amazing man and I am lucky to have known him."

Friends and loved ones took to social media to mourn Mitchell, a Valley View resident who served six years in the Tennessee Army National Guard.

In addition to Keira, he had a child with Herrera and two children from a previous relationship. His Instagram profile included the hashtags #proudfather and #soldier, and his Facebook page showed off his interests in the Dallas Cowboys and snakes, with pictures of him holding a variety of pythons.

Hate loosing childhood friends. So many memories mane from Peewee to high school football. Show your family love whenever you can. Don't wait because it might be to late. Put ya pride down...R.I.P Brandyn Mitchell #BlueDevilFamily — Quitin Sparkmon (@By_The_Stars) May 21, 2018

The mother of two of his children, Asia Platt, wrote on Facebook that she was at a loss after learning of Mitchell's death. But the man she still considered one of her best friends died helping someone else, she said.

"You went out a hero, saving the life of someone you cared about," she said. "That is the greatest gift one could receive."

Quitin Sparkmon, a childhood friend from West Memphis, Ark., tweeted that he lost a brother and teammate in Mitchell.

"Show your family love whenever you can," he wrote. "Don't wait because it might be too late."

Herrera told the Star-Telegram that she and Mitchell had just made plans to get married next year, with hopes of honeymooning in Europe.

"He was an amazing father," she said. "He was loved and will be missed. No matter what, he was a hero."

A GoFundMe account has been set up to help Mitchell's family with funeral costs.