I've read that Lycanthropy strains can be cured with magic like "Remove Curse" pretty easily.

If someone catches it, and ends up having a child some time later... would the child be born with the curse, and it manifests later in life?
Or would it still be the same kind, and easily just as curable with normal magic?

I wasn't sure if passing on the curse by accident via child-creation would lead to a harder-to-remove lycanthropy curse, or if it wouldn't show up until adulthood/certain age.

A natural born lycanthrope can't be cured except with a Wish spell, as explained in the Monster Manual.