Instruction:

Baby Yoga by Francoise Barbira Freedman.

Baby and Toddler Yoga (DVD) by Francoise Barbira Freedman.

ItsyBitsy Yoga: Poses to Help Your Baby Sleep Longer, Digest Better, and Grow Stronger, by Helen Garabedian.

Baby Om: Yoga for Mothers and Babies, by Laura Stanton and Sarah Perron.

Yoga Mom, Buddha Baby: the Yoga Workout for New Moms, by Jyothi Larson and Ken Howard.

Yoga for the Special Child, by Sonia Sumar (addresses special needs).

Infant Massage:

Yoga kids, by Marsha Wenig (great ideas for play/songs/stories).

I Can't Believe It's Yoga for Kids! by Lisa Trivell.

Yoga in Action, by Bobbie Kalman.

Just for Fun:

Little Yoga: A Toddler's First Book of Yoga, by Rebecca Whitford.

Babar's Yoga for Elephants, by Laurent de Brunhoff.

Storytime Yoga: Teaching Yoga to Chidlren Through Story, by Sydney Solis.

My Daddy is a Pretzel: Yoga for Parents and Kids, by Baron Baptiste.

Yoga Pretzels: 50 Fun Yoga Activities for Kids and Grownups, by Tara Guber & Leah Kalish.

Wai Lana's Little Yogis Fun Exercise Kit (book & DVDs/videos), by Wai Lana.