Carole,
If you go to the Demarest webpage at www.demarests.com they have done the decend tracking work for the des Marets families through 12 generations, starting with David des Marets and Marie Sohier. I haven't done any side tracking, only the primary and secondary tracks that lead to David Jr and Samuel (sons of David and Marie des Marets). Right now, it's only an assumtion that the Canadian lines are primarily from David Jrs. lines trek North.
Minus the tracking numbers, here is my line:

1. David des Marets, 1620, married to Marie Sohier

2. David Demarest Jr, Dec. 24, 1651 married to Rachel Cresson in NYC

3. Benjamin Demarest married to Elizabeth De Groot in Hackensack, NJ (Kindermack)

4. David Demarest married to Marrityn Ackerman in Hackensack, NJ

5. Petrus Demarest, married to Sara Demarest

6. David Demarest, still researching

7. Earl Orville Demarest married to Anna Maria Ackert in Redhook, NY

8. William Francis Demarest married to 1. Ida Savage in Fonda, NY 2. Margret Rutt (Root) in Fonda, NY

9. Frank Lester Demarest married to Louisa Kirpins in Gloversville, NY

10. Harold Lester Demarest married to Katherine Thackery in Schenectady, NY

11. Robert Emmett Demarest Sr., Mar 31, 1934, married to Harriette Lakin in Colorado.

Children:
Robert Emmett Jr. 1959
Mark Allen 1960
Denise Anne 1961
Jeffery Edward 1963
Danielle Alise 1971

12. Robert Emmett Demarest Jr., married to Theresa Ritner in Toms River, NJ Aug 8, 1981.

13. Shannon Eileen Demarest, other, Joshua Crate
Matthew Robert Demarest married to Holly Sprague
Adam Paul Demarest married to Shannon Thompson

14. Shannon’s Children
Aiden Rose Demarest
Mya Jade Crate
Lucas Gabriel Crate

Matthew’s Children
Paige McKenzie Demarest

Adam’s Children
Tyler Braidon Demarest
Kaiden Christopher Demarest

With the exception of my youngest brother and sister and gens 13 and 14, all the info was obtained from the documents on the Demarest web-site. Yours should be just as easily tracked if you have some dates to start with. You'll be able to track back and forward from them...

Bob