What are some things that you had to learn thru parenting experience that other/new parents should know?

There are a plenty of books, magazines, and websites offering a ton of information to mothers, but some things aren’t mentioned often enough either because they are overlooked or they can only really be learned through experience.

These things can be related directly to parenting or children, or can be something not so directly related to parenting, such as household tips, medicine, pets, or a variety of other factors that in some way will effect the child.

It can be advice that is only relevant to babies, preschoolers, even all the way up to teenagers, or it may be something that can effect kids of all ages.

It can even be directly related to a physical or psychological condition of either the child (diseases, illnesses, or behavioral problems) or the mother (postpartum depression or physical problems that originated or were aggravated by giving birth or parenting).

What things did you learn the ‘hard way’ or through experience while parenting/birthing that you did not previously know of or hear about? Or is there something that you feel is important for other parents to know that doesn’t get talked about much?