It turns out that at the end of this episode that the Chalice of Mome (or possibly a replica) is made by Timmy as a present to his mother since the word Mome is actually "Mom-E" (a pun on the word "mommy")
The headgag is different in the UK version. It is usually an apple in the US, but in the UK, it's a cow.
This is just one of three episodes (the others being "Christmas Everyday" and "Certifiable Super Sitter") where the headgag was different depending on the country.
This is the only episode in the series that does not have "The Fairly OddParents In" on the title card.