A Sundance festival hit involving sperm donation and the year's biggest blockbuster cartoon aren't just the two best films of this summer. Oddly, they're also eerily alike.

If you go "The Kids Are All Right" 4 out of 5 stars Stars: Annette Bening, Julianne Moore, Mark Ruffalo, Mia Wasikowska Director: Lisa Cholodenko Rated R for strong sexual content, nudity, language and some teen drug and alcohol use. Running Time: 104 minutes

The R-rated "The Kids Are All Right" stars Hollywood grande dames Annette Bening and Julianne Moore as longtime life partners who run into trouble when their teenage children decide to find their anonymous biological father Mark Ruffalo. The G-rated "Toy Story 3" is about, well, toys. But both movies are original, gentle comedies of family love with thoroughly developed characters. Both unfold around with the same rite of passage -- when the oldest child, a graduating senior, prepares to leave the nest for college. And both climax with unforgettable, heart-wrenching scenes as these matriculating freshmen part from their loved ones and metaphorically say goodbye to childhood.

Obviously "Kids," a sophisticated and dialogue-rich slice of bourgeois bohemian life, doesn't have special effects or animated action. Instead, this adults-only indie delves perplexing real life challenges like existential midlife crisis, marital ennui, and adolescence.

Director and co-writer Lisa Cholodenko is known for her observant eye. Like her "High Art" and "Laurel Canyon" -- two other wonderful movies -- her latest again finds wit and pathos in everyday human weakness. She also illuminates specific, modern subcultures and makes them universal.

For example, the fact that the spouses here -- Bening's hilariously uptight doctor Nic and Moore's offbeat artist Jules -- are lesbian is beside the point. The way they deal with an infidelity in their relationship, after two decades together, and their parental worries could apply to anyone.

The conflict in their mildly neurotic clan begins when 18-year-old Joni (Mia Wasikowska of "Alice in Wonderland," better suited to this low-key piece) and her 15-year-old brother Laser (Josh Hutcherson) contact the sperm donor they never knew. Paul (Ruffalo) is a single, immature restaurateur who is delighted to suddenly find himself with these cool kids. Nic and Jules aren't so thrilled about their bonding. And they have good reason to be concerned.

But the presence of an outsider will have an unexpected effect. Perhaps ironically to some, it's a resolution that upholds traditional family values.

Ruffalo gives a pitch-perfect performance at once sexy, vulnerable and sleazy as the main source of drama in the story. But this entertaining, expressive movie works so well because all of the performances in "Kids" are all right.