All the Little Animals (1999)

An emotionally challenged young man named Bobby runs away from home in order to escape his abusive stepfather who has killed his pets. He meets an old man, Mr. Summers, who spends his time traveling and giving burials to animals that have been killed by cars. Bobby, also having an affinity for animals, becomes friends with the old man and aids him in his task.

Unfortunately the movie All the Little Animals is not yet available on HBO Max.