PROVIDED HOWEVER, that in case any of my said children predecease the survivor of my wife and myself,leaving issue alive,such issue shall stand in the place of such deceased child of mine and take,per stirpes and equally among them,if more than one,the share of my residuary estate which said child of mine would have taken if he or she had survived me. In the event that any of my children predecease the survivor of my wife and myself leaving no issue,the deceased child's share of my estate shall be divided equally among my surviving children.