Before I hand things over to the Expert, I have a some personal experience with this topic. My wife has red hair, and I have brown hair with some facial red hair, so what are the chances that are kids would have red hair. Would the chances be 30% or 50%, what if I told you 100%. All three of my children have red hair. Our oldest, our daughter has Auburn hair, our oldest son has dark red hair and our youngest son has strawberry-blonde hair. Even though there are statistics that you can go by, I'm convinced that you can never count on it being a perfect system.
As far as eye color, the two older kids ended up with hazel eyes and the youngest has green-hazel eyes. My wife has green eyes and I have hazel eyes. Now for the Expert...
Red hair: Red hair is often a very simple dominant/recessive case. What I mean is that a certain gene called MC1R comes in two forms, a non red (R) and a red (r) form. R is dominant over r.
As a redhead, you are rr, you will always pass a red hair gene down to your kids. But what about your husband? He could be either an RR or an Rr, it is impossible to know right now.
Well, that isn't strictly true. If he could have one gene, MC1R, sequenced, he would have a pretty good idea about whether or not he is a carrier. Unfortunately, no one is currently offering this service*. Some, but not all carriers of the red hair gene have freckles so this can be a hint. But there are people without freckles who carry a red hair gene too (me, for example).
So, let's say your husband is a carrier. Then we are in a similar position to blue eyes. You will always pass on an r version of the MC1R gene. All of your kids will at least be carriers.
Your husband has a 50-50 shot of passing on the red hair version, r. Those kids that get the r from your husband will be redheads. Those who get the R will be carriers.
If your husband is RR, then most likely none of your kids will end up redheads. They will all be carriers of the red hair gene (from you) but not redheads themselves.
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Source: Dr. Barry Starr, Stanford University (www.thetech.org)