Very occasionally exactly the same abnormalities will be found in more
than one member of a family, but more commonly it is the tendency for heart
disease to occur which is stronger in some families. We have already seen
(above) that a tendency is present in every family to a very small extent.
The risk of another child with some form of heart disease being born in a
family which already has one member with heart disease is about one in
thirty to one in fifty. This is also the risk for children if one of their parents
had a heart problem as a child, whether or not it was corrected. If both
parents had heart problems, or the parents are closely related, the risks are
very much higher.
Thus the risk of two members of the same family being born with
heart disease are slight.