[fix] key error (#12257)

diff --git a/erpnext/manufacturing/doctype/bom/bom.py b/erpnext/manufacturing/doctype/bom/bom.py
index 1e723b1..a06645a 100644
--- a/erpnext/manufacturing/doctype/bom/bom.py
+++ b/erpnext/manufacturing/doctype/bom/bom.py
@@ -591,7 +591,7 @@
 		frappe.throw(_("BOM {0} does not belong to Item {1}").format(bom_no, item))
 
 @frappe.whitelist()
-def get_children(doctype, parent=None, is_tree=False):
+def get_children(doctype, parent=None, is_root=False, **filters):
 	if not parent:
 		frappe.msgprint(_('Please select a BOM'))
 		return