Eating less or just stopped growing?

Hi Everyone.  Not sure if I'm being overly worried but thought I might post here for some insight.

I have a female cat a little over 1 year named Marble. Weighs a little less than 9 pounds.

She is very talkative and playful.  Infact very night she cries and runs to her toybox demanding play before bedtime.  We also have another cat that she chases around the house.

We feed her 1/4 cup of dry food (Spots Stew, grain free) in the morning and a little less that 1/4 dry +  spoonful of Wellness wet food.
This morning and just now tonight my husband who feeds her commented that she only ate about half her food.  Normally she is a slow eater but she doesnt leave food unless its a few pieces.

Her energy has not changed at all and she is still very cuddly and talkative.  Unless my husband mentioned less eating you'd never know.

Should I be concerned?  Should I wait a few days to see if this continues before going to the vet?

My husband thinks because she is over a year maybe she has finally stopped growing so she doesnt want as much.

I think you can wait a couple days and see how her appetite is. Not eating as much every once in a while isn't usually a cause for concern. If she keeps it up, you can weigh her daily and if she doesn't lose any weight, you're husbands theory is probably correct. If she is losing some weight, taking her in wouldn't be a bad idea just to make sure there's nothing else going on. It could just be that she's gotten bored with her food and you might need to try a new flavor or add some toppers.