has anyone else found it weird that when you breed two of the same themed pets the offsprings color changes even though both parents have the same exact coloring?

On Sylestia, there's what's known as color swing, and it applies to themed pets. While the colors are nearly the same, they're not the exact same.

Such as;

and

They're the same theme, but there colors are slightly different;

Scarlette's Colors:

EC: R:245 G:027 B:106

C1: R:242 G:236 B:241

C2: R:242 G:243 B:240

C3: R:008 G:007 B:001

GC1: R:179 G:123 B:029

GC2: R:146 G:085 B:021

GC3: R:010 G:006 B:007

MC1: R:199 G:049 B:045

MC2: R:190 G:038 B:043

MC3: R:243 G:227 B:195

AC1: R:002 G:005 B:009

AC2: R:116 G:000 B:005

Vegeta's Colors:

EC: R:246 G:048 B:134

C1: R:244 G:247 B:252

C2: R:242 G:242 B:248

C3: R:009 G:006 B:008

GC1: R:174 G:118 B:019

GC2: R:116 G:053 B:006

GC3: R:011 G:015 B:013

MC1: R:186 G:035 B:035

MC2: R:173 G:028 B:023

MC3: R:255 G:242 B:212

AC1: R:000 G:005 B:002

AC2: R:103 G:018 B:014

If you read through their colors, their colors differ slightly from one another's, not being the exact same despite being the same themed pet. So if they were to breed an offspring, their slight differences in colors would apply to their offspring as well due to their color swing.

I hope this post helps to explain a bit. ^^

It's caused by the slight color swing seen in themed pets. A smidge more red here, a tiny bit more green there, and the resulting offspring can end up... kind of weird.

I believe tamed themes have it a little worse with a wider margin of variance, while exclusives are closer to true.

Lighter colors tend to be the most heavily impacted, since even a subtle variance can be highly noticable. If your pastel purple is suddenly a little more greenish, it's a big change. Meanwhile if your bright and saturated purple gets a little more green you'll barely notice.

Years ago it was significantly worse, and Krin has confirmed before that the color swing is intended.

thanx everyone