Question: What does Adam Sandler say after that kid throws up at the beginning? Does he say "I think I saw a boob come out of him"? (sorry, but that is what it sounds like.).
Question: How did Robbie's parents die? Is it ever mentioned?
Chosen answer: How his parents died is never mentioned.
Answer: He didn't feel that it was his place to interfere in their relationship. Especially as he had feelings for Julia himself and didn't want to make it look like he was sabotaging their relationship for his own benefit.