As Herbert says - no numbers etc unless they were used at the time. (In some places "the younger" and "the elder" may be appended, but that can also be confusing when the same terms are used for parents and children who have the same name.)
You can also place a warning, such as the one I use here, or (I believe I saw someone say the other day) set up a rejected merge.
Whichever method you decide to use, be sure to have documentation and as full an explanation as you can in the biography.