Dr. Stoppard's book has been out of print for a long time (having been originally published in 1991 with a 2nd ed in 2001) but some libraries have it and you can usually find a used copy online. I was originally introduced to the text by a friend and colleague while we were developing a music and movement family program for kiddos 4-14 months of age (divided into smaller groups: 4-8mo, 8-12mo, 10-14mo). I needed a resource to help me know very specifically the developmental abilities of young, young kids so I could better design curriculum to meet them where they were and support their continued growth and development. This book was that resource. It was so good I didn't want to give it back. So I bought my own copy.
What I like about the book is that it really focuses on development as a progression of skills, capabilities, and interests. It addresses typical development birth thorough 4-5 years (focusing much more heavily on early development). The book includes chapters on "Parent as Teacher," "The Normal Course of Development," "Factors Affecting Development," "Simple Tests" (1990s lingo for simple assessments that can help you know that your kiddo is developing appropriately), "Tools for Learning," "The Special Child," and "Your Child and School." Also, the book is SUPER accessible -- TONS of photographs, short sections (making it easy to reference, rather than requiring that you read straight through if you don't have time), and in the development section it lists (in a simple, easy-to-follow format) typical developmental age, skill or developmental task, what you as an adult can do to support, and one or two sample activities to support the development of that skill.
I recommend it to parents and find that I still put it out when in need of a good guide, even after having first read it in 2004.