A large variable that comes to mind that can influence both the IV and DV is a mother's physical health. Poor physcial health on the mother's part may cause her to become preoccupied with things not at all realted to her baby. This by itself may change the attachment style of the infant. Additionally, the infant's well-being later in life may be hurt by being exposed repeadily to someone of poor health.
I think that is an interesting point, but I only agree with it to some extent. I understand that the mother may have added stress and show some neglect because of her health, which could affect the baby's attachment. However, depending on the degree of severity of the illness, a mother's will can be surprisingly strong when it comes to her children, so she would most likely still try to be there for the child. Mother's make all kinds of sacrifices for their children, and I'm sure most would still spend time with their kids instead of worrying about themselves if they were sick.
