In addition to just being a darn good film, Mrs. Doubtfire gave us two great gifts. One was the launch of Mara Wilson, a wonderful child actor who grew up into one of the most insightful and brutally honest young women to ever speak out on the dangers of child stardom.
The second was a story about how terrible parental alienation can be. The lesson of Mrs. Doubtfire is that when there are two appropriate parents, children do best when both parents are as involved as often as possible. And appropriate should not be related to which parent has the better job, house, or handsome significant other.
No one had ever heard of parental alienation in 1993. But Mrs. Doubtfire dove head first into the concept. Miranda, the children's mother, repeatedly insults and degrades her children's father, and fought for full custody even though the children adored him. Daniel, played by Williams, is devoted to his children but is a struggling actor who can't compete with his architect ex who has much better lawyers and a nicer looking lifestyle. He ends up with visits every other weekend and a social worker from the courts assigned to the case to report to. Eventually he is able to get a job as the children's nanny by disguising himself as an old English woman named Mrs. Doubtfire. Send the kids to their room before you verbally bash their father, Mrs. Doubtfire so wisely advises Miranda. Even when Daniel does everything the judge asks of him, he still loses custody and has his visits restricted to monitored.
Eventually, Miranda comes around and allows Daniel to be more involved in the children's lives despite the custody order. Not bad for 1993.