diff --git a/src/LibreQoS.py b/src/LibreQoS.py
index a0b9e08c..7104d937 100755
--- a/src/LibreQoS.py
+++ b/src/LibreQoS.py
@@ -1456,6 +1456,39 @@ def apply_effective_runtime_circuit_overrides(subscriberCircuits):
 
     return overlay_count
 
+
+def findBandwidthMins(data, subscriberCircuits):
+    """Raise each node's minimum bandwidth to cover its own circuits and children.
+
+    Mutates ``data`` in place. Returns the summed minimums of all circuits and
+    child nodes in the tree so callers can propagate them to a parent node.
+    """
+    totalDownload = 0
+    totalUpload = 0
+    for elem in data:
+        minDownload = 0
+        minUpload = 0
+        for circuit in subscriberCircuits:
+            if elem == circuit['ParentNode']:
+                minDownload += circuit['minDownload']
+                minUpload += circuit['minUpload']
+        if 'children' in data[elem]:
+            minDL, minUL = findBandwidthMins(data[elem]['children'], subscriberCircuits)
+            minDownload += minDL
+            minUpload += minUL
+        if 'downloadBandwidthMbpsMin' in data[elem]:
+            data[elem]['downloadBandwidthMbpsMin'] = max(data[elem]['downloadBandwidthMbpsMin'], minDownload)
+        else:
+            data[elem]['downloadBandwidthMbpsMin'] = max(data[elem]['downloadBandwidthMbps'], minDownload)
+        if 'uploadBandwidthMbpsMin' in data[elem]:
+            data[elem]['uploadBandwidthMbpsMin'] = max(data[elem]['uploadBandwidthMbpsMin'], minUpload)
+        else:
+            data[elem]['uploadBandwidthMbpsMin'] = max(data[elem]['uploadBandwidthMbps'], minUpload)
+        totalDownload += minDownload
+        totalUpload += minUpload
+    return totalDownload, totalUpload
+
+
 def refreshShapers():
 
     # Starting
@@ -1832,31 +1865,8 @@ def refreshShapers():
                         genPNcounter = 0
         print("Generated parent nodes created")
 
-        # Find the bandwidth minimums for each node by combining mimimums of devices lower in that node's hierarchy
-        def findBandwidthMins(data, depth):
-            tabs = '   ' * depth
-            minDownload = 0
-            minUpload = 0
-            for elem in data:
-                for circuit in subscriberCircuits:
-                    if elem == circuit['ParentNode']:
-                        minDownload += circuit['minDownload']
-                        minUpload += circuit['minUpload']
-                if 'children' in data[elem]:
-                    minDL, minUL = findBandwidthMins(data[elem]['children'], depth+1)
-                    minDownload += minDL
-                    minUpload += minUL
-                if 'downloadBandwidthMbpsMin' in data[elem]:
-                    data[elem]['downloadBandwidthMbpsMin'] = max(data[elem]['downloadBandwidthMbpsMin'], minDownload)
-                else:
-                    data[elem]['downloadBandwidthMbpsMin'] = max(data[elem]['downloadBandwidthMbps'], minUpload)
-                if 'uploadBandwidthMbpsMin' in data[elem]:
-                    data[elem]['uploadBandwidthMbpsMin'] = max(data[elem]['uploadBandwidthMbpsMin'], minUpload)
-                else:
-                    data[elem]['uploadBandwidthMbpsMin'] = max(data[elem]['uploadBandwidthMbps'], minUpload)
-            return minDownload, minUpload
         logging.info("Finding the bandwidth minimums for each node")
-        minDownload, minUpload = findBandwidthMins(network, 0)
+        findBandwidthMins(network, subscriberCircuits)
         logging.info("Found the bandwidth minimums for each node")
 
         # Child nodes inherit bandwidth maximums of parents. We apply this here to avoid bugs when compression is applied with flattenA().
diff --git a/src/test_libreqos_shaping_inputs.py b/src/test_libreqos_shaping_inputs.py
index 83f681b6..e1ff471e 100644
--- a/src/test_libreqos_shaping_inputs.py
+++ b/src/test_libreqos_shaping_inputs.py
@@ -522,6 +522,164 @@ class TestLibreQoSShapingInputs(unittest.TestCase):
         self.assertEqual(missing_parents, {})
 
 
+class TestFindBandwidthMins(unittest.TestCase):
+    def test_sibling_minimums_do_not_accumulate(self):
+        def build_network(child_order):
+            children = {
+                "Crew": {
+                    "downloadBandwidthMbps": 100,
+                    "uploadBandwidthMbps": 100,
+                    "downloadBandwidthMbpsMin": 20,
+                    "uploadBandwidthMbpsMin": 20,
+                },
+                "Guest": {
+                    "downloadBandwidthMbps": 178,
+                    "uploadBandwidthMbps": 88,
+                    "downloadBandwidthMbpsMin": 60,
+                    "uploadBandwidthMbpsMin": 20,
+                },
+                "Infra": {
+                    "downloadBandwidthMbps": 82,
+                    "uploadBandwidthMbps": 30,
+                    "downloadBandwidthMbpsMin": 1,
+                    "uploadBandwidthMbpsMin": 1,
+                },
+                "MGMT": {
+                    "downloadBandwidthMbps": 30,
+                    "uploadBandwidthMbps": 15,
+                    "downloadBandwidthMbpsMin": 10,
+                    "uploadBandwidthMbpsMin": 4,
+                },
+            }
+            return {
+                "Site": {
+                    "downloadBandwidthMbps": 189,
+                    "uploadBandwidthMbps": 69,
+                    "downloadBandwidthMbpsMin": 120,
+                    "uploadBandwidthMbpsMin": 60,
+                    "children": {name: children[name] for name in child_order},
+                }
+            }
+
+        circuits = [
+            {"ParentNode": "Crew", "minDownload": 10, "minUpload": 10},
+            {"ParentNode": "Crew", "minDownload": 10, "minUpload": 10},
+            {"ParentNode": "Guest", "minDownload": 60, "minUpload": 20},
+            {"ParentNode": "Infra", "minDownload": 1, "minUpload": 1},
+            {"ParentNode": "MGMT", "minDownload": 10, "minUpload": 4},
+        ]
+
+        for child_order in (
+            ["Crew", "Guest", "Infra", "MGMT"],
+            ["MGMT", "Infra", "Guest", "Crew"],
+        ):
+            network = build_network(child_order)
+            totals = LibreQoS.findBandwidthMins(network, circuits)
+
+            self.assertEqual(totals, (91, 45))
+            self.assertEqual(network["Site"]["downloadBandwidthMbpsMin"], 120)
+            self.assertEqual(network["Site"]["uploadBandwidthMbpsMin"], 60)
+            generated = {
+                name: (
+                    node["downloadBandwidthMbpsMin"],
+                    node["uploadBandwidthMbpsMin"],
+                )
+                for name, node in network["Site"]["children"].items()
+            }
+            self.assertEqual(
+                generated,
+                {
+                    "Crew": (20, 20),
+                    "Guest": (60, 20),
+                    "Infra": (1, 1),
+                    "MGMT": (10, 4),
+                },
+            )
+
+    def test_child_minimums_roll_up_once(self):
+        network = {
+            "Site": {
+                "downloadBandwidthMbps": 100,
+                "uploadBandwidthMbps": 100,
+                "downloadBandwidthMbpsMin": 0,
+                "uploadBandwidthMbpsMin": 0,
+                "children": {
+                    "Tower": {
+                        "downloadBandwidthMbps": 50,
+                        "uploadBandwidthMbps": 50,
+                        "downloadBandwidthMbpsMin": 0,
+                        "uploadBandwidthMbpsMin": 0,
+                        "children": {
+                            "AP-1": {
+                                "downloadBandwidthMbps": 25,
+                                "uploadBandwidthMbps": 25,
+                                "downloadBandwidthMbpsMin": 0,
+                                "uploadBandwidthMbpsMin": 0,
+                            },
+                            "AP-2": {
+                                "downloadBandwidthMbps": 25,
+                                "uploadBandwidthMbps": 25,
+                                "downloadBandwidthMbpsMin": 0,
+                                "uploadBandwidthMbpsMin": 0,
+                            },
+                        },
+                    },
+                    "Tower-2": {
+                        "downloadBandwidthMbps": 40,
+                        "uploadBandwidthMbps": 40,
+                        "downloadBandwidthMbpsMin": 0,
+                        "uploadBandwidthMbpsMin": 0,
+                    },
+                },
+            },
+        }
+        circuits = [
+            {"ParentNode": "Tower", "minDownload": 4, "minUpload": 1},
+            {"ParentNode": "AP-1", "minDownload": 10, "minUpload": 2},
+            {"ParentNode": "AP-2", "minDownload": 5, "minUpload": 1},
+            {"ParentNode": "Tower-2", "minDownload": 7, "minUpload": 3},
+        ]
+
+        totals = LibreQoS.findBandwidthMins(network, circuits)
+
+        self.assertEqual(totals, (26, 7))
+        self.assertEqual(network["Site"]["downloadBandwidthMbpsMin"], 26)
+        self.assertEqual(network["Site"]["uploadBandwidthMbpsMin"], 7)
+        self.assertEqual(
+            network["Site"]["children"]["Tower"]["downloadBandwidthMbpsMin"], 19
+        )
+        self.assertEqual(
+            network["Site"]["children"]["Tower-2"]["downloadBandwidthMbpsMin"], 7
+        )
+        self.assertEqual(
+            network["Site"]["children"]["Tower"]["children"]["AP-1"][
+                "downloadBandwidthMbpsMin"
+            ],
+            10,
+        )
+        self.assertEqual(
+            network["Site"]["children"]["Tower"]["children"]["AP-2"][
+                "downloadBandwidthMbpsMin"
+            ],
+            5,
+        )
+
+    def test_missing_minimum_keys_use_download_minimum(self):
+        network = {
+            "Leaf": {
+                "downloadBandwidthMbps": 100,
+                "uploadBandwidthMbps": 50,
+            }
+        }
+        circuits = [{"ParentNode": "Leaf", "minDownload": 150, "minUpload": 40}]
+
+        totals = LibreQoS.findBandwidthMins(network, circuits)
+
+        self.assertEqual(totals, (150, 40))
+        self.assertEqual(network["Leaf"]["downloadBandwidthMbpsMin"], 150)
+        self.assertEqual(network["Leaf"]["uploadBandwidthMbpsMin"], 50)
+
+
 class TestFirstRunSinceBoot(unittest.TestCase):
     def setUp(self):
         temp_dir = tempfile.TemporaryDirectory()  # nosec B108