I talked to a counselor yesterday about helping my child deal with missing his father. The counselors answer? It's a hard situation but you are absolutely doing the best thing for your child by keeping him away from someone who is actively addicted to drugs and disrupting the peace and tranquility that should be in your life.
What to tell the child:
Your daddy loves you but your daddy has an illness. We cannot call him right now. He will get in touch with us when he is able. It's hard to understand because you are in kindergarten. You may feel disappointed or angry about this and thats ok. You'll understand more when you are older.
I love you and it's my job to take care of you no matter what. You have nothing to worry about.
Now. Would you like to go for a walk or get an ice cream cone?