A child invader?

I have a dim membory of an episode where there a scene with a paperboy who the audience (but none of the characters) saw was an alien spying on someone.

And I think that the end credits said something like "Paperboy - Teddy Quinn".

However the IMDB page for Teddy Quinn doesn't list an invaders episodes.

Sod oes anyone remember any episodes with aliens disguised as children?