If Shigeru isn't a parent himself and is using this manga as a sort of vent for all his baby-related experiences and traumas, I would be very surprised.
Krugger said: Now we learn day care tips as well, at this rate I might have to add danbooru to my resume
Just FYI, Koyama-san made sure to emphasize in the Pixiv description that he frequently makes errors when drawing "Mamange", and it is NOT intended to teach proper childcare. CYA and all.
Aaaaaaah!★L... Lady Yuyuko?!Okay, there, there.Oh, dear!What are you smiling about?!Hmmm...but there are lots of kids who eat like her at her age, so I think it's all right...Check to make sure she chews properly!...and pay attention to her stools and choose ingredients to make sure her diet isn't too unbalanced!Chew ChewNoooooooo!
Grinnn
...and if she eats a lot, give her lots of vegetables and carbohydrates to make her feel full...As long as you watch the speed at which she eats...