Seasonal Leafeon retexture for the cat, inspired by ImXTooNinjaxX's Leafeon mod, and using that sprite sheet. The sprite sheet is originally from Pokémon Mystery Dungeon: Explorers of Darkness/Time. Requires Smapi and Content Patcher.

I referenced the last artwork in the images, but I reversed image searched and couldn't find the artist. 

Added an optional orange version for fall!

Please let me know if there are any bugs. I'll try to fix them, but may not be able to because this is my first mod. 
I noticed that sometimes when you leave your house in the morning, your pet is not there, but it reappears when you reenter and exit the house again. I'm not sure how to fix that. If you have an idea of what the problem is, please tell me!

Seasonal Eeveelutions (Sylveon, Leafeon, Flareon, Glaceon) Done!

Future plans:
Seasonal Bulbasaur
Seasonal Eevee? With flower crowns? Maybe idk
Feel free to suggest more!

Other mods pictured:
Stardew Valley Expanded and Remastered Immersive Farm 2 by FlashShifter
Climates of Ferngill by Sakorona
Dynamic Night Time by Sakorona
Flower Valley by jina2ya
Hobbit Holes by Sonreirblah
Yellog's wood fence by Yewon_Nam
Yellog's Wood craftables by Yewon_Nam
Dusty pethouse for Flower Valley by superdadidou (for Karmylla's Immersive Maps, I just replaced my pethouse with the texture)
Victorian Mailbox by Eemiestardew
Junimo Scarecrow from Ran's Farm Decor by ranfuu
Magica Trees by ERRORcauser
Missy's Shirts by MissyDiabolical
Seasonal Fantasy Hats by paradigmnomad
Witchy Hats by 7yrsofbadluck and contrarequiallas for the cp edition
Easy Petting by CeruleanSpirit
Vintage Interface by ManaKirel
Isa's Pastel Weapon Retextures by Isalamiii
Ali's Flower Grass NEW ALTERNATIVE VERSION by strawberrymilk95
Just a new map recolor by Eemiestardew and minervamaga for cp edition
Nightmare's Weapon Retextures by zcsnightmare
Nightmare's Tools Retextured by zcsnightmare
Pethouse Re-skin to match Yellog's Buildings by EscaPlays, original Pethouse by Taelende
Wizard Style House by naeldeus