John McConnell and Maureen Brennan who play Mr and Mrs Muskie are actually married in real life.
'Young Pete', played by Connor Jones, and 'Pete' played by Mark Wahlberg both had many black dots drawn on their faces during filming for the football flashback in order for their faces to be matched perfectly in post-production.
"Meatball" is played by a three-year old Bernese Mountain Dog. Prior to filming, he had completed his AKC grand championship, an obedience title, several rally obedience titles, and a dock diving title. After filming completed, he added his BMDCA and Canadian draft titles and several others, becoming a Versatility Dog in both the US and Canada.
The film was inspired by writer/director Sean Anders' experience adopting through Seneca Family of Agencies' Kinship Center.
The movie was inspired by the real events from the life of writer/director Sean Anders.
Instant Family's story is based on the real life experience of director Sean Anders. Sean has adopted 3 Hispanic children.
Isabela Moner and Mark Wahlberg previously starred together in Transformers: The Last Knight (2017).
This was the third collaboration between director Sean Anders and actor Mark Wahlberg. Their previous two films were Daddy's Home (2015) and Daddy's Home Two (2017).
Mark Wahlberg played an adopted man in "Four Brothers." And a dad trying to reconnect in "Daddy's Home"