These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Calling the Old Man Out: Many, many times, by several of the characters. Also a female version when Rose scolds her mother.
Continuity Cavalcade: At the end of Season 3, with a lot of supporting characters and patients of the week going to Andy's Appreciation Party.
Foe Yay - Dr Abbott takes every chance to mock Andy Brown. Amy jokes, "You so have a boy crush on him."
Harsher in Hindsight: Ephram's comment about Nina's surrogacy that he "doesn't understand how anyone could just give up a baby" becomes so much harsher three years later.
Love-Obstructing Parents: Only occasionally, as Andy heavily opposed Ephram and Madison at first (he was very fond of Madison but didn't approve of their being together because of the age difference) and Harold didn't like Tommy at all. Otherwise averted: Rose and Harold were warm and welcoming towards Colin, Ephram and Hannah, as were Andy towards Amy and Stephanie and Hannah's mother towards Bright. Edna also encouraged her daughter to date Andy, and Andy's father quickly saw Nina as someone who could make his son happy. It could be argued that, in the case of Andy dating Linda, Harold was a love-obstructing older brother.
Missing Mom: A lot actually, to the point that Rose and Nina are the only significant exceptions. Otherwise: Julia dies, Edna was absent for a large part of Harold's childhood, Rose's mother was psychologically abusive to the point of bullying, Hannah and Kyle had rocky relationships with their mothers, Reid's mom is portrayed as emotionally distant (until she had a very strong wake-up call), it's mentioned that Andy's mother died when he was relatively young (though possibly already a doctor), Irv's daughter also resented her mother, Madison's was distant enough that she wasn't told about the pregnancy, Brittany's mother is out of the picture (she lives with her father and step-mother), several patients also have a dead or disappeared mother... by comparison, there are lots of dads around.