Does any new parent, even if you're not a first-time parent, ever really know what to do?

Does any new parent, even if you're not a first-time parent, ever really know what to do?

新父母，即使你不是第一次为人父母，真的知道该怎么做吗?

-- Robert John Downey Jr. 小罗伯特·约翰·唐尼