NEW YORK CITY, NEW YORK: ‘Good Morning America’ star Michael Strahan was recently quizzed by fans after he celebrated his son Michael Strahan’s Jr's birthday by putting up an Instagram post to wish him.

The 51-year-old ‘GMA’ host shared a birthday message with an unseen picture of his son, who just turned 29.

However, while a few fans wished his son on his birthday, others were completely puzzled to find out that the ex-NFL star is a father to a boy. For them, Strahan only had “three daughters.”

Michael Strahan’s birthday post for son confuses ‘GMA’ fans

The ‘GMA’ star is blessed with four children, two of them - Michael Strahan Jr. and Tanita Strahan, from his first marriage, and twin girls - Isabella and Sophia, from his second marriage.

Although some fans only knew about his three daughters and were taken aback to learn that he has a son.

Strahan took to Instagram and shared a sweet birthday message for Strahan Jr.

He captioned the post, “Happy birthday to my son, @mstrayjr!!! Wishing you an amazing day. Yes, I must say I wish I could grow a beard like you LOL. Enjoy it MJ!!”

In the first snap, Michael stood in a dark gray shirt and black shorts atop a cliff. He wore a backpack with socks sneakers and a baseball cap to accessorize.

It looked like the 29-year-old may have just begun or was planning to go on a hike. In the second snap, Strahan and his son posed with other members of the family, including daughter Tanita.

Fans who were unaware of the ‘GMA’ star’s son's existence flocked in the comments to express their amazement.

One wrote, “Just thought you had daughters,” while a second said, “I didn't know you had a son”

A third said, "Wait, you have a son?” while other fans wished his son on his big day.

A fan wrote, “Happy birthday king!!!!!!! "Fine" like FATHER”, and another followed through and said, “Happy Birthday to your handsome son and wishing him many lire blessings”.

Michael Strahan attended ‘GMA’ co-host Robin Roberts’ wedding

Recently, Strahan attended Robin Roberts and Amber Laign's wedding.

The former NFL star was just one of the many morning TV personalities at Robin's wedding.

Michael, clad in a crisp black and white suit, headed to the event with girlfriend Kayla Quick by his side.

In one snap, he was seen posing next to her with one arm around her waist, holding her close. Quick wore a black dress with thin straps tied at her shoulders as both smiled for the cameras.