The first time Lily (Barbie Ferreira) sits down with a new counselor in Bob Trevino Likes It, we hear only snippets of the backstory she lays out in rambling, rapid-fire detail. Even so, it’s evident it’s a dark one: “Despite what my father says, I’m pretty sure it was not all my fault,” she says of being abandoned by her mother at age four. And it’s made only more heartbreaking by the way she presents it — with the chipper, matter-of-fact cadence of a woman who’s been carrying the pain for so long she’s become totally inured to it.

As Lily wraps up her spiel with a smile, she’s startled to realize the counselor has burst into tears; in the end, Lily has to comfort her about how sad Lily’s own life is. But that counterintuitive mix of tones is Bob Trevino Likes It in a nutshell. Like its heroine, the comedy can be bright and bouncy and frequently funny. But also like her, it’s secretly a tearjerker, and never more effectively than when it’s at its very sweetest.

Certainly, its heroine has a lot to cry about. In fact, the film’s very first scene sees her sobbing over a flirty text from her boyfriend that was clearly intended for someone else. In a rage, she types out “LOSE MY NUMBER YOU JERK.” Then she erases the message, and instead replies with an upbeat “no prob! :)” It soon becomes apparent that her doormat tendencies are well-honed from a lifetime of dealing with her father (an excellent French Stewart), a narcissist who rarely misses an opportunity to remind her that she ruined his life just by being born — or to play the victim whenever she dares stand up for herself.

But Bob Trevino Likes It is not here to wallow in Lily’s misery. The film draws its emotional power not from watching its characters break, but from letting them start to heal. After a particularly nasty fight with her dad, Lily tries to find him on Facebook and connects instead with a middle-aged contractor who happens to have the same name. In no time at all, Lily comes to regard Bob (John Leguizamo) as a sort of surrogate father figure, and Bob to treat Lily like the daughter he never had. As they grow closer, each helps the other to mend at long last from the blows that have upended their lives.

If there’s a quibble to be had with Bob Trevino Likes It, which is inspired by the experiences of writer-director Tracie Laymon, it’s that the bond between Lily and Bob seems a bit easy. Their jagged edges fit together as neatly as pieces of a puzzle, and Lily’s growth proceeds with few of the stops and starts and backslides that tend to mark even the healthiest evolutions in real life. For his part, Bob is portrayed as a nigh-angelic figure who always seems to know exactly the right thing to do or say to set Lily on the right path. The few other characters who populate the film, including Daphne (Lauren “Lolo” Spencer), Lily’s live-in employer, and Jeanie (Rachel Bay Jones), Bob’s wife, exist solely to nudge Bob and especially Lily along their arcs, rather than to embark on journeys of their own.

And yet it’s hard to argue that Bob Trevino Likes It would necessarily have worked better as a rawer or darker or more sprawling movie. As it is, it succeeds beautifully on its own terms as a love letter, or perhaps a thank you note. Bob and Lily’s connection might be idealized, but Laymon still takes care to ground them in moments that feel authentic, performed by actors who seem incapable of striking a false note. Ferreira is radiant as Lily, who carries herself like a skittish puppy — bursting with so much love she hardly knows how to contain herself, but also terrified to let her guard down lest she get kicked again. Leguizamo tempers her high-key energy with a mellower decency and just a hint of sorrow. Genial as Bob is, a wariness in his demeanor suggests something is missing from his life, even if the shape of that something is not immediately obvious. Together, Leguizamo and Ferreira share a chemistry as warm and lively as the campfire their characters share over one meteor-filled night.

Beyond its perfectly cast leads, the film’s true secret weapon is its disarming sense of modesty. Bob and Lily’s relationship might look, especially at first, like nothing all that thrilling. He likes her posts on Facebook, having noticed that no one else seems to respond to them. She asks about his childhood, and opens up about hers. When her toilet breaks down, Bob drives over to fix it without hesitation. Grand cinematic gestures these are not. But it’s plain from their faces how much it means to be able to give and receive these little acts of care. As they break down each other’s defenses, Bob Trevino Likes It chips away at ours too. By the time I was watching Lily snuggle with a puppy, in a Bob-directed exercise to help her move past a formative childhood trauma, I was crying almost as hard as she was.

In time, Lily, fortified by the sort of sincere, selfless, steady love she never received growing up, is able to process the damage her father has left in his wake. And Bob, having been jolted out of his numbness, is finally able to open up about the painful and difficult feelings he’s kept locked away for so long, first to Lily and then eventually to Jeanie. The Lily we leave at the end of Bob Trevino Likes It is far from perfectly healed, and a bring-on-the-waterworks final scene reminds us that life’s not done dealing her blows just yet. But she is a Lily who, at long last, can bring herself to believe the words Bob impressed upon her in one of their most meaningful conversations: “We’re all a bit broken. But you’re gonna be fine.” For a girl whose story once reduced a therapist to tears, that’s no small feat.