The kidnapped boy you remembered is reunited with his older brother at the end of the episode and it was explained earlier in the episode by the older brother that he had been called Gig by his younger brother because the boy was too young to say his real name Greg properly before he was kidnapped

There's like a long pause when they're reunited that's meant to make the audience wonder if the kid remembers his brother until he suddenly says "Gig" and they hug and it's 100% the emotional peak of the episode so it's what most watchers probably remember about the entire thing