It's got to be something in your house or car because it's effecting your whole family. All of you should probably be checked for allergies. Do you have any mold in your house? Did you make any changes around the time this all started? Bath soap, laundry soap, anything you can think of? Do you have a gas furnace? You might want to have your house checked for mold and have the furnace checked. This is strange that it started with your daughter 8 years ago but is just starting to effect the rest of your family now.
I believe it is either some type of mold or possibly something with the furnance. If possible, see if you can have the home checked for toxic molds. As for the furnance, check the home for radon levels. You can buy a radon kit at a home improvement center and/or have a professional come out and check the furnance.
Keep us posted.
Check home for toxic mold. Cheapest kit can be bought at Home Depot for about 10 bucks. Best testing is to hire an engineering or remediation company but this can cost thousands. Would start with the kit first. Am a victim and survivor of toxic mold poisioning in my home. My entire family became ill and I almost lost my life. The horrible health effects of toxic mold is being unnoticed and misdiagnosed by the medical community. We lived a nightmare for over a year. It will require a doctor trained in toxic mold to treat you, which there are only a handful, approximately 4 that I know of in the U.S. The rest of the doctors, allergists and so on will not be able to help you and tell you that mold cannot make you that sick.....don't believe them. If you have any questions please ask and I will answer. I want to help others. God bless you and your family.