In "Sweet Pepper" Pepper has a crush on another animal and tries to change herself to impress him. In the My Little Pony: Friendship Is Magic episode "Simple Ways" Rarity does the same thing. Both Pepper and Rarity are voiced by Tabitha St. Germain and both episodes aired on the exact same day.
Russell is not the first character Samuel Vincent played who is either a hedgehog or a neat freak (though he only did Sonic's singing voice; the rest of the time it was Jaleel White)
Name's the Same: Russell Ferguson shares his name with a Krump dancer who won So You Think You Can Dance season 6. May or may not be an inversionnote That is, the former may or may not have been deliberately named after the latter.
Lampshaded with The Igors and Karinas in that Shake-A-Leg.
Zoe Trent and Penny Ling's singing voices are done by Kylee Epp and Laura Hastings.
Heidi's singing is done by Shylo Sharity. Seeing that Heidi Klum was based in Los Angeles, this makes sense.
Post-Script Season: While the show never had much of a Myth Arc, season four was this for the series as the finale of season 3 ended on a big spectacle that involved the return of a lot characters implying that the writers felt that that was was going to be the last season before Hasbro gave them one more. The finale of S4 and the series as a whole felt like any other episode of the show with the only big thing to happen being Roger, Blythe's father, revealing he always knew that she (and her mother) could talk to animals. The creators of the show actually wanted a season 5 before they got word that the show was canceled due to low toy sales.
Relationship Voice Actor: Nicole Oliver and Tabitha St. Germain voice sisters Zoe Trent and Gail Trent after previously voicing sisters Celestia and Luna in My Little Pony: Friendship is Magic.note This may have even been done on purpose.
What Could Have Been: Except for Sunil, most of the pets originally had different names. Zoe was Lady Ra Ra, Penny was Lolly, Pepper was Jasmine, Minka was Margo, Russell was Winston and Vinnie was Tony.
Writer Revolt: "Topped With Buttercream" sure comes off this way. It's undoubtedly meant to promote the candy-themed LPS toys (which seem to be half the toyline), but it's not flattering to the concept at all. Characters mention off-hand the detrimental effects of a diet rich in sugar. The pets get high on sugar and turn into twitchy, paranoid, delusional savages. Buttercream seems to have been permanently damaged by sugar to the point where she has multiple verbal and physical tics. By the end of the episode, the pets run in fear from sugary snacks (although they get over it in future episodes).