Do Doulas Replace Dads?

Absolutely not. I can not speak for every doula out there, but I consider the role of a doula is one of a supporter, not only of the mother and baby, but of the family. 

I provide this support in practical ways to the father by keeping an open line of communication, answering questions he might have about his new role and by "stepping out" from between him and baby whenever possible to allow him to bond with his new child.

Dads and Doulas: Support During the Postpartum Period:

http://www.dona.org/pdfs/Dads%20and%20Postpartum%20Doulas.pdf