We are often asked whether a misspelling in a Will, or an incorrect address of a beneficiary, or similar, might invalidate a Will, or a gift in a Will. The answer is that they do not.
There are only a relatively few things that can invalidate a Will. Most significantly these include not having the signing by the Will maker witnessed properly, and the Will maker him or herself not having the appropriate legal capacity to make the Will (for instance as a result of dementia).
A misspelling of the name will not invalidate a gift, as long as it is clear who the Will maker intended to benefit. For example, a gift to “my nephew Graham Jones” will be valid if the nephew’s name is actually Graeme Jones (as long as there is not another nephew with this name!).
If there were nephews with each of these names, then the gift would probably fail for uncertainty, but this would not invalidate the whole Will, just this gift.