diff --git a/rtamt/syntax/node/arithmetic/addition.py b/rtamt/syntax/node/arithmetic/addition.py
index 2cb4d4a1..dc13d9a9 100644
--- a/rtamt/syntax/node/arithmetic/addition.py
+++ b/rtamt/syntax/node/arithmetic/addition.py
@@ -21,9 +21,6 @@ def __init__(self, child1, child2):
         """
         super(Addition, self).__init__(child1, child2)
 
-        self.add_child(child1)
-        self.add_child(child2)
-
         self.in_vars = child1.in_vars + child2.in_vars
         self.out_vars = child1.out_vars + child2.out_vars