Boy sings 'Coco' song at late baby sister's altar in emotional viral video

WATCH: Boy Sings "Coco" Song At Baby Sister's Altar

A Texas boy is reminding people that love lives on forever, no matter what.

Alex Deais, 4, of San Antonio said goodbye to his 4-month-old baby sister, Ava Lynn, last May. For her first birthday, he sang a special song for his sister, which his mother, Stephanie Deais, caught on camera.

>> Read more trending news

The emotional video shows Alex strumming a tune on his plastic guitar while he sings "Remember Me" from the movie "Coco." He didn't know he was being recorded because he was facing a photo of his sister.

>> Watch the video here

Ava Lynn's first birthday would have been Dec. 30.

Alex's parents posted the video to Twitter, where it has been viewed more than 1 million times.