Contact comfort theory was pioneering in the 1950's but now it seems to be common knowledge. It makes sense yet there are still multiple theories as to why children and other animals instinctively want comfort. A person would think that children bonds to who feeds them. As the book mentioned this is not the case for children and it is not the case for animals. My sister has five birds, a species researchers nickname " 2 year olds with can openers on their face". The birds are always fed by our mother , however when their cages are opened they fly towards our ( me and sister ) dad. Our dad gives them attention, and kisses , and pets their feathers while they perch on his shoulder for hours. The birds gets playtime from him and nothing but food and water from mom. In other words birds, monkeys and toddlers react similarly to parental figures. One question is not answered by the theory. Why don't babies bond with their mothers more than fathers if they are first and foremost held by mothers? More importantly why does the bond of mother and child rapidly decline after 18 months? It makes me wonder if children know, on some level, that the parent they hug would step with nourishment if the caregiver with the food disappeared.
I definitely think that children, generally, bond more with their mothers than fathers. Being the oldest of six kids, I've watched five kids grow up with a particularly strong relationship with our mother. Not that they didn't bond with our father, but in most family systems, mothers tend to be the caretakers and fathers tend to be the enforcement. In situations where roles are reversed, the bonds are also different. This really shows how much comfort matters.