We spilled a bunch of proverbial ink explaining what a terrible father Harry is to Albus (check out Harry or Albus' character analysis for more details). But what about Ginny? How are her parenting chops?
The answer is that it's kind of hard to say, because we never see a scene that shows her interacting with Albus. This doesn't mean she's ignoring her bouncing baby boy. It just means we can't judge her parenting skills.
All her scenes are with Harry, where she comes across as pretty passive. For example, when Harry bullies McGonagall into tracking his son with the Marauder's Map, the stage directions tell us, GINNY looks at HARRY, unsure of what he's become (2.10.24).
But she doesn't say a thing to him.
Over the course of the play, though, she starts finding her voice. When Draco admits he was lonely and envious of Harry's friendships with Ron and Hermione, Ginny chimes in,
GINNY: I envied them too. (2.15.9)
That's a moment that humanizes Draco more than Ginny, though, because she doesn't really need our sympathy at this point in the story.
After Harry's second failed talk with Albus, Ginny tells him,
GINNY: I can forgive you for one mistake, Harry, maybe even two, but the more mistakes you make, the harder to forgive you it becomes. (3.15.29)
If that sounded like an ultimatum, it wasn't. Ginny continues talking to her husband, and finally gives him some specific advice about specific love:
GINNY: Harry, you'd do anything for anybody. You were pretty happy to sacrifice yourself for the world. He needs to feel specific love. (4.9.17)
But what would "specific love" look like to Albus? Does Ginny know? If so, why is she being Dumbledore-levels of cryptic and not just telling him what that is? Or does Harry need to find this out for himself, regardless of whether or not Ginny has an idea?
Ginny isn't in the play enough to answer these questions. Maybe she's off spending time with their other two kids.