I disagree on this one. You can’t expect a step parent to love/value somebody else’s kids as much as they love/value their own.
My oldest child is from my wife's first marriage. I met my wife when the baby was 8 months old and I've never called her my "step" daughter. Here we are 41 years later...
Baloney. I’d, and always have, treated my stepdaughters equally to my biological daughter, as well as my adopted son. Any man who doesn’t is an ass.