Talk about pulling at the heartstrings.
This little 4 year old boy, was caught on camera singing to his baby sister in heaven. In May, his 4-month-old sister Ava Lynn died after being diagnosed with hydronephrosis.
This boy is seen singing "Remember Me," from the Disney movie Coco, to a picture of his sister.
The video was posted on Twitter and has been viewed thousands of times.
Hydronephrosis is a condition that affects the kidneys.