Bind Google Organizational Chart from multiple tables in ASP.Net

I tried to draw Google Org Chart but i have 2 tables

his structure of chart

// Process 1 ----- Practice 1 ------ Activity 1 / Activity 2 / Activity 3

// Process 2 ----- Practice 2 ------ Activity 4 / Activity 5

dataTable.Columns.AddRange(new DataColumn[] { new DataColumn("processID", typeof(int)), new DataColumn("name", typeof(string)), new DataColumn("practiceID", typeof(int)),
new DataColumn("activityID", typeof(int)) });
 
dataTable.Rows.Add(1, "process 1", 0 , 0);
dataTable.Rows.Add(1, "practice 1", 1, 0);
dataTable.Rows.Add(1, "practice 2", 2, 0);
dataTable.Rows.Add(1, "activity 1", 1, 1);
dataTable.Rows.Add(1, "activity 2", 1, 2);
dataTable.Rows.Add(1, "activity 3", 1, 3);
dataTable.Rows.Add(1, "activity 4", 2, 4);
dataTable.Rows.Add(1, "activity 5", 2, 5);