Original sentence: An additional criticism of the parenting styles research is that parenting has been shown to be part of a bi-directional relationship between parent and child.For instance, harsh parents may produce harsher children through the mechanism of genetic transmission of these traits
Edited sentence: For instance, harsh parenting may produce harsher children through the mechanism of genetic transmission of these traits.The final and most important criticism of the parenting styles research is that parenting has been shown to be part of a bi-directional relationship between parent and child