Mark Ruffalo

Dominick Birdsey / Thomas Birdsey

Melissa Leo

Concettina Ipolita Tempesta 'Ma' Birdsey

Rosie O'Donnell

Lisa Sheffer

Archie Panjabi

Dr. Patel

Kathryn Hahn

Dessa Constantine

John Procaccino

Ray Birdsey

Rob Huebel

Leo

Michael Greyeyes

Ralph Drinkwater

Gabe Fazio

Shawn Tudesco / Dominick and Thomas Acting Double

Harris Yulin

Father Lavie

Bruce Greenwood

Dr. Hume

Marcello Fonte

Domenico Onofrio Tempesta

Sue Jean Kim

Dr. Yup

Michael Simon Hall

Stuart Feinstein

Gina Costigan

Mrs. O'Meara

Steven Cox

Boyfriend of Dr. Hume's Daughter

MorningStar Angeline

Nabby Drinkwater's Wife

Al Linea

Abruzzi

Richard Fitch

Mill Foreman

Amy Lynn Stewart

Merciful Mother

Guillermo Díaz

Sergeant Mercado

Marylouise Burke

Librarian

Brian Goodman

Al

Sandra Berrios

Social Worker at Hatch

Laura Silverman

Kristin

Christine Parks

Humanities Department Chair

Morgan Sullivan

Office Buddy

Jake Robards

Landlubbers (voice)

Michael Genet

Thomas' Surgeon

María Gonzalez

Ma's Oncology Nurse

A.C. Peterson

Gene Diogenes

Christopher J. Hanke

Thad

James Quattrochi

Bus Driver

Rachel B. Joyce

Jeanette

Paul Coleman

Support Group Counselor

Brandon J. Dirden

Kyle's Dad

Katt Masterson

Doreen

Jason Furlani

Larry Penn

Annie Fitzgerald

Miss Hanker

Kate Grimes

English Professor

Acahkos Johnson

Penny Ann Drinkwater

Joseph Ragno

Henrey Rood

Jaiden Klein

Marie Sexton

Charlie Reina

Channy

Violet Adams

Bunny Borsa

Oliver Patnode

Otero

Chelsea Sheets

Brunette

Matt Helm

Young Leo