diff --git a/i3bar/src/child.c b/i3bar/src/child.c
index 2b0fb780..c0a56661 100644
--- a/i3bar/src/child.c
+++ b/i3bar/src/child.c
@@ -169,7 +169,7 @@ void start_child(char *command) {
     ev_io_start(main_loop, stdin_io);
 
     /* We must cleanup, if the child unexpectedly terminates */
-    child_sig = malloc(sizeof(ev_io));
+    child_sig = malloc(sizeof(ev_child));
     ev_child_init(child_sig, &child_sig_cb, child_pid, 0);
     ev_child_start(main_loop, child_sig);