China's Lunar Birthday Fortune Telling to See the Hit Child

I remember seeing a picture of boys and girls born in Qing dynasty, which is calculated according to the lunar calendar. Actually, it's not fortune telling, it's just a rule. Not 100% accurate, accurate to 90% to 95%, but there are rules to follow. I wonder if I can find it online. Foreigners are not allowed in. It is estimated that the physique of foreigners is different from that of us in China.