The Fairly OddParents is a Nickelodeon cartoon created by Butch Hartman. It's a minor meme on the TimmyTurnersGrandDad channel.
The cartoon is about Timmy Turner, a 10 year old kid who had a miserable life until he was granted two fairy godparents, Cosmo and Wanda. Its theme song was composed by Ron Jones and Butch Hartman. It ran from 2001 to 2017 and is generally considered to have declined in quality. However, it was popular in its early years, leading to one YouTube user (now better known as GilvaSunner) to create a since-terminated channel called TimmyTurnersDad, which would eventually inspire the name and avatar for TimmyTurnersGrandDad.
As the name of TimmyTurnersGrandDad references The Fairly OddParents, it has naturally been referenced in some of TTGD's rips. The first rip that features the theme song as a joke is "Jenka 1 (Beta Mix) - Cave Story". Additionally, most album covers and lore videos imitate the show's art style, and the channel banner displays the Turner residence. It is however a minor meme, and isn't frequently used.
An event based on The Fairly OddParents would be referenced in TTGD's Mind Blowers and a unused profile picture for the event was included in the bonus media in TTGD's Mind Blowers: 5th Anniversary Special. Icky Vicky Day was the first The Fairly OddParents event and had rips featuring songs related to Vicky, an character featured in The Fairly OddParents.