Definitely had ppd just as covid lockdown began where I live. I think I'm educated enough on early child development and have enough resources and financial ability to have accomplished the opposite of this study. We did sign language and books from the start, despite ppd and global crisis. It's equal to feedings in families that have the resources. I don't think everyone has the same understanding or luxuries. Every skill a child has takes so many weeks or months of preparation and incremental steps before mastery. We need to do a better job in the USA with teaching parents how to support literacy and numeracy skills from age 0-5, simple behavioral support, and maybe just do a better job with infant and toddler care overall.