Stepfather II: Make Room for Daddy (1989)

Jerry Blake (Terry O'Quinn) escapes an insane asylum and winds up in another town, this time impersonating a marriage counselor. Now he seems to have found the perfect future wife (Meg Foster), with a stepson (Jonathan Brandis) who loves him. However, other people try to get in his way to marry her. They are interfering. One by one, Jerry eliminates anyone who stands in his way to a perfect family.