How are bellybuttons formed?

My sister keeps on describing me that when you are still in your mother's stomach in attendance is a string attached to your bellybutton and your mother. Then when you are born, the doctor cuts the string that was attached to you and your bellybutton. So I am in recent times asking you for the answer because I am really confused about how your bellybutton is formed. the umbilical cord is a gangway for all the nutriets the mother provides to budge to the baby. when the little one is born, the doctors tie the umbilical cord and cut it. the excess material will leak off after a week or so and the belly button is produced.
Your sister is primarily right.
As a baby develops inside the mother, he or she floats contained by fluid inside the mother's womb. While the baby is within there, he or she can't breathe nouns or eat food. That's where on earth the umbilical cord comes in. The umbilical cord is a flexible tube that carry oxygen and nutrients from the mother to the baby. It also carry wastes away from the infant back to the mother, so she can carry rid of them. Your belly button marks the spot where on earth your umbilical cord was once attached.
New born babies do not inevitability an umbilical cord anymore. The doctor cuts the umbilical cord and a tiny stump is left. When this stump falls sour after a few weeks, the baby is disappeared with a belly button.
A belly button is a defacement left after the umbilical cord is cut after birth.