Board Thread:Naruto Gaiden/@comment-26084508-20150617064121/@comment-26530217-20150625033504

Simple theory, when Sakura gave birth to Sarada, then something happen and the child only can be save by Karin healing expertise. In between of that process, Karin DNA need to mixed up inside the child to make sure the child is save.

Then here come the child name Sarada. Carrying three DNA which is Sakura, Sasuke and Karin.