Anytime the wacky relative shows up, it usually does not lead to a good episode. You should not introduce a character like this, even if was just a one-off appearance, in the 4th episode. That is way too early for a show that is already about a huge, extended family. This episode did feature some funny parts, but like is usually the case with Modern Family, the episode was just so predictable. The minute Dylan broke out the guitar you knew it was going to be an inappropriate song. If you did not know that, watch more television!
Some good moments, but not that great an episode.