Yes you can.

How to;
On the side bar menu, select Members Module as shown below.

A drop down menu appears.
On the menu, click on membership management and select list members.

Path to follow;
Members>Membership Management>List Members

Once selected a list of all members as shown below.

On the member list, click on edit to view a specific member`s profile.

Once selected, a form with the member details appears.
On the form, scroll down to the Next of Kin details as shown below.

Click on Add Next of Kin.

A form appears as shown below.

Fill in the form and click on Save Changes.