I looked Amy's hight on the fandom Sonic wiki and it says she's 2

Sonic Dream Team, Sonic Wiki Zone

Classic Sonic, Heroes Wiki

Sonic the Hedgehog, Love Interest Wiki

Sonic & Friends' is a New Animated Series, Here's the Official

Amy Rose, Archie Sonic Online Wiki

Amy Rose (There's Something About Amy)

Marine the Raccoon, Sonic Wiki Zone

Sonic the Hedgehog 2 (film), Sonic Wiki Zone

Sonic the Hedgehog IDW: Amy's 30th Anniversary Issue - Official

Sonamy, Shipping Wiki

Sonic the Hedgehog, Heroes Wiki

Nimue, Sonic Wiki Zone

Amy Rose (Sonic Adventures), Sonic Wiki Zone

Sonic X (Anime) - TV Tropes

Amy Rose (Sonic X), Sonic Wiki Zone