Thank you for the quick replies. We are not attempting to take everything with us, but will be checking a bag for each of them as my wife and daughter are going to be travelling for about a month.
Another question that I know need to ask is regarding the personal bag. It states that it can be "a briefcase, laptop or handbag" on the BA website. But I am also assuming that a small backpack complying with the personal bag sizes will be allowed as this bag. Is this correct?