I think having children can offer both mothers and fathers the opportunity to develop new strengths. And the extent to which that occurs probably depends on lots of factors. The parents' respective strengths/weaknesses, the children's personalities, the culture in which the kids are raised, etc.
I have seen my ex show a lot of F with our son, for example. Not his strong point, but there has been some growth there, and since he works with kids, it has probably helped him in his career.