Most of us who have or have had Children started teaching them the basics as they were in their formative years. We taught them to say “please” when they wanted something, but we also taught them to say “thank you” upon receiving a blessing.
It wasn't something they were born with, but the more we taught them not only with our words but also with our examples, they began to use these powerful words. And for that, we are thankful!
The Bible tells us in Psalm 107:8-9 – 8 Let them give thanks to the LORD for his unfailing love and his wonderful deeds for mankind, 9 for he satisfies the thirsty and fills the hungry with good things.