The only thing realistic about this movie was the judge at the end
Not really the judge, but morsoe his condemnation of Daniel and his dressing up like a woman to infiltrate his wife's home in order to interact with his children.
Of course this is just a movie and it's supposed to be funny and emotional, but in real life this would be a very disturbing tale if it actually happened. There'd be nothing funny about it, it'd just be plain creepy. It wouldn't be this funny, wacky story full of shenanigans of a man finding himself in several sticky situations in which he has to cover up the fact he's a not really a woman all the while spending time with his children who had no idea (at first) that he's really their father.
So the judge condemning him at the end and calling his behavior disturbing and taking his children away and calling for supervised visits is the most realistic thing about this movie, as that is exactly what a court of law and a judge would think.
I saw this movie in 2008 and I vowed never to see it again.
On another note, Miranda was an awful mother to just keep her children away from their Dad for really no good reason, and having to "think about it" when he wanted to take his kids to and from school. She had no reason to keep them away from her.
In real life though, if a seemingly good dad was willing to dress up as a woman to infiltrate his family's' home that's another story, then she has every right to keep her kids away from him but let's keep with in the context of the film. But if this was a true life story it'd be very disturbing.
Only people with money say that money doesn't matter.