The athlete, 48, celebrated Anthony's 55th birthday on Saturday by sharing two sweet posts on his Instagram Story.
“Once a brother always a brother ????,” Beckham wrote alongside a black and white photo of himself and Anthony. “Happy Birthday man, Love Ya."
In another image celebrating his longtime friend, Beckham and Anthony smiled as they posed with glasses of red wine in front of a fireplace decorated with stockings during the holidays.
“We laugh as one ????,” he captioned the smiling snapshot.
Earlier this month, Beckham surprised the Latin pop singer as he received a star on the Hollywood Walk of Fame.
“So proud of my brother another incredible achievement and so well deserved,” Beckham wrote in a post on Instagram. “Honoured to be there for you ???? Love you man @marcanthony ⭐️.”
His arrival at the dedication ceremony was a shock to Anthony, who teared up as Beckham made a touching speech in honor of his friend.
“So I first met Marc 20 years ago when I was playing for Real Madrid. Probably not a very cool thing to say, but I was very starstruck when I met Marc because on the way to every Real Madrid game I used to listen to his music. I now dress a little bit like him. I learned salsa for one man only — but please don’t tell my wife,” Beckham said in the speech, per Access Hollywood.
He continued, “But when we met, we immediately had a special connection. I knew that I had a friend for life. Over the years our friendship has grown, and Marc is family – godfather to my son, Cruz, and someone I love to spend time with.”
In July, Anthony welcomed a baby with wife Nadia Ferreira, and Beckham was one of the first people to meet the newborn.
The "You Sang to Me" musician shared a sweet photo of Beckham kissing the baby’s foot on Instagram. In his caption, he wrote, "Tío David nos vino a visitar. Que bendición," which translates to "Uncle David came to visit us. What a blessing."
At Anthony’s wedding to the model in January, Beckham was a groomsman and stood beside his longtime friend as he said, “I do.”
In a video montage from the nuptials posted by Ferreira, 24, and Anthony on Instagram after the wedding, Beckham appeared to make a toast to the couple at the reception.
Beckham's wife, Victoria Beckham, also designed Ferreira’s bridesmaids dresses.
In an Instagram post congratulating the couple on their marriage, the designer wrote, “We love you both so much and it was such an honour to be part of your special day."