They actually figure it out pretty fast, they just don't give him the water immediately. Translations:

Kid: Hey, that's mine, that's not yours!

Mom: He's trying to get the water.

Kid: He's thirsty.

Other kid: Maybe give him some by putting it in the cap.

Kid: Yes, that's what I'm doing.

Other Kid: In the cap and then put it down.

Kid drops cap

Other Kid: Ugh, Thijs! (Kid's name)

dad picks it up and lets bird drink

Dad: Go away Thijs, don't scare him, let him drink.

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