INSPIRED by the experiences of writer-director Sean Anders, Instant Family is a surprisingly sweet and touching comedy drama about foster parenting, which delivers its core messages with sincerity and tear-filled eyes.

The opening hour of Anders’s picture, co-written by John Morris, mines a steady supply of chuckles from the misadventures of a happily married couple who welcome three troubled tykes into their ordered home.

Blood flows when a 10-year-old boy accidentally takes a basketball and then a baseball to his cherubic face. Nerves fray as the only bathroom struggles to accommodate three additional bladders and the beauty regime of a teenage girl.

Anders’s light touch and occasional splashes of syrupy sentiment give way to painful home truths in a poignant second half. Instant Family earns its heartfelt emotional release by focusing intently on the inner turmoil of children who have been discarded and sometimes starved of affection and need someone to provide them with stability and a safe harbour from the darkness of the past.

Pete Wagner (Mark Wahlberg) and wife Ellie (Rose Byrne) renovate tired properties.

The couple have never seriously discussed raising children until an argument between Ellie and her sister Kim (Allyn Rachel) prompts a serious debate about foster parenting.

Pete and Ellie naively undergo a training course run by sassy social workers Sharon (Tig Notaro) and Karen (Octavia Spencer), who repeatedly hammer home the physical and emotional toll that lies ahead.

Once Pete and Ellie have qualified, they offer a home to troubled 15-year-old Lizzy (Isabela Moner) and her siblings, 10-year-old Juan (Gustavo Quiroz) and six-year-old Lita (Julianna Gamiz).

Relatives rally around the exhausted couple, including Pete’s straight-talking mother (Margo Martindale), who makes child-rearing seem so effortless.

Instant Family charms by stealth. Byrne and Wahlberg possess a winning combination of cluelessness and caring, and the latter wrings genuine tears from his scenes with gifted young co-stars. Notaro and Spencer deliver pithy one-liners with expert timing, then share the film’s emotional heavy-lifting as self-doubt takes a heavy toll on the Wagners’ marriage. A family isn’t defined by the blood flowing through its veins but by words and deeds, and in this respect, Anders’s picture proudly wears its heart on its sleeve.

RATING: 6/10