NEW YORK • A video of a visually impaired nine-month-old boy who sees his father clearly for the first time ever, through special glasses, is melting hearts across the world.

Little Reagan Caldwell was all smiles as he got a good look at his father Brandon, a captain in the United States Air Force, who had just returned home to New York from a stint in Antarctica.

Reagan was infected with Group B Strep (GBS) shortly after he was born, said his mother Amanda. As a result, he came down with sepsis, meningitis and other illnesses, and was rushed to an intensive care unit in a hospital, the Caters News Agency reported.

Mrs Caldwell quit her job as a teacher to care for Reagan. Then, her husband was deployed to Antarctica in what she said "was the hardest deployment yet by far".

Before he returned, his little boy had received the special glasses to improve his vision as part of a recovery regime that also includes physical and speech therapy.

"I was never told this (GBS) could make my baby sick after leaving the hospital," Mrs Caldwell told ABC7 news.

"I want mums to ask questions and do research on it. And if you think there is something going on with your baby, take him to the paediatrician or the emergency room."

In the video, Capt Caldwell is still in uniform when he picks up his baby boy and entertains him with "patty-cake, patty-cake", part of a nursery rhyme.

Reagan peers at him, bouncing excitedly in his arms. Seconds later, the little boy rests his head on his father's chest.

"You can see how hard it was for Brandon to be away from Reagan by the emotion he showed when he finally had him in his arms again," Mrs Caldwell told ABC7 news.

"Reagan did not skip a beat and is loving having daddy back home."