I think the baby will have dark brown hair, it is also possible that her/his hair will be a reddish brown. Sometimes the traits of the parents mix, so if a parent has blue eyes and the other green, the child could have blue green eyes. The colour of a baby's eyes and hair is given by the genes of his parents, those genes can be recessive or dominant. Blue eyes and light coloured hair is given by recessive genes, while brown hair and eyes are given by dominant genes. Dominant genes are more likely to be inherited in most cases. I mean, if a lady has blue eyes and blonde hair and she marries a gentleman with brown hair and brown eyes the baby is more like to inherit his father's hair and eye colour. It is almost certain that the grandparents of the baby from his/her mother's side have light hair and blue eyes. So, in order for the baby to inherit blue eyes, one of his grandparents from his mother's side has to have blue eyes. But I am only telling you my opinion, I am not a geneticist, plus you never know how the baby will turn out to be. If your baby doesn't inherit your husband's red hair, still one of your grandchildren could have red hair.