Do I get any benefits from petting my chicken?

I recently unlocked the chicken coop and then I bought a chicken. I noticed that I can pet the chicken once per day and a little heart displays above its head.

I've done this every day for almost an entire season and I'm not seeing any benefits from it. Does petting it serve any sort of food production purposes or is it merely for fun?

Petting your livestock (basically interacting with it like you would with a villager) increases its happiness. As your livestock becomes happier (visible by the info screen that comes up after you try to interact with it a second time), it has a higher chance of producing better versions of their normal produce, such as Large Milk, Large Egg, or Large Goat's Milk.

Basically the Chicken looks forward to being petted by you. When it does gets touched it gets happier and is more encouraged to produce better quality food.

A thing not mentioned in other answers: When you pet your chicken inside a barn/coop, you also gain 5 experience points towards the Farming skill.

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