Sometimes. Our species reproduces sexually so we aren't identical to our parents. If our parents have a handicap then we'll possibly get that disability but if a cell has a defect the off-spring will surely get it. Our parents give us genetic material with DNA from both sides. For example, a kid can get obesity from their mother or father so in the same sense you could get Alzheimer's from a parent or relative.
It can be, but it can also just develop in the person. I don't wanna scare you, but genetic Alzheimer's usually skips a generation so your mom and her siblings probably wont get it, but you probably will.