diff --git a/cmd/orphan.go b/cmd/orphan.go
index 7b5f9eb..b033d52 100644
--- a/cmd/orphan.go
+++ b/cmd/orphan.go
@@ -4,6 +4,7 @@ package cmd
 import (
 	"fmt"
 	"os"
+	"slices"
 
 	"github.com/boneskull/gh-stack/internal/config"
 	"github.com/boneskull/gh-stack/internal/git"
@@ -59,7 +60,10 @@ func runOrphan(cmd *cobra.Command, args []string) error {
 
 	node := tree.FindNode(root, branchName)
 	if node == nil {
-		return fmt.Errorf("branch %q is not tracked", branchName)
+		node, err = disconnectedNode(cfg, branchName)
+		if err != nil {
+			return err
+		}
 	}
 
 	// Check for children
@@ -90,3 +94,46 @@ func runOrphan(cmd *cobra.Command, args []string) error {
 
 	return nil
 }
+
+func disconnectedNode(cfg *config.Config, branchName string) (*tree.Node, error) {
+	trackedBranches, err := cfg.ListTrackedBranches()
+	if err != nil {
+		return nil, fmt.Errorf("branch %q is not tracked", branchName)
+	}
+	if !slices.Contains(trackedBranches, branchName) {
+		return nil, fmt.Errorf("branch %q is not tracked", branchName)
+	}
+
+	childrenByParent := make(map[string][]string)
+	for _, branch := range trackedBranches {
+		parent, parentErr := cfg.GetParent(branch)
+		if parentErr != nil {
+			continue
+		}
+		childrenByParent[parent] = append(childrenByParent[parent], branch)
+	}
+	for parent := range childrenByParent {
+		slices.Sort(childrenByParent[parent])
+	}
+
+	visiting := make(map[string]bool)
+	var build func(string) *tree.Node
+	build = func(name string) *tree.Node {
+		node := &tree.Node{Name: name}
+		visiting[name] = true
+		defer delete(visiting, name)
+
+		for _, childName := range childrenByParent[name] {
+			if visiting[childName] {
+				continue
+			}
+			child := build(childName)
+			child.Parent = node
+			node.Children = append(node.Children, child)
+		}
+
+		return node
+	}
+
+	return build(branchName), nil
+}
diff --git a/e2e/orphan_test.go b/e2e/orphan_test.go
index 50793fc..4cf9803 100644
--- a/e2e/orphan_test.go
+++ b/e2e/orphan_test.go
@@ -53,3 +53,64 @@ func TestOrphanForceClearsPRBaseOnDescendants(t *testing.T) {
 		t.Errorf("expected feat-b stackPRBase cleared, got %q", v)
 	}
 }
+
+func TestOrphanDisconnectedBranchIsAllowed(t *testing.T) {
+	env := NewTestEnv(t)
+	env.MustRun("init")
+
+	// Create the branch chain main -> feat-a, then manually delete the
+	// parent link so feat-a's recorded parent ("missing-branch") is not
+	// itself a tracked branch. This mirrors the scenario in #116 where
+	// the parent is no longer valid and `gh stack orphan` previously
+	// refused to orphan the current branch.
+	env.MustRun("create", "feat-a")
+	env.CreateCommit("feat-a work")
+	env.Git("config", "branch.feat-a.stackParent", "missing-branch")
+
+	if env.GetStackConfig("branch.feat-a.stackParent") != "missing-branch" {
+		t.Fatal("expected feat-a parent override to land before orphan")
+	}
+
+	result := env.Run("orphan", "feat-a")
+	if !result.Success() {
+		t.Fatalf("expected orphan of disconnected branch to succeed, got exit %d stderr=%q", result.ExitCode, result.Stderr)
+	}
+	if v := env.GetStackConfig("branch.feat-a.stackParent"); v != "" {
+		t.Errorf("expected feat-a stackParent cleared after orphan, got %q", v)
+	}
+}
+
+func TestOrphanDisconnectedBranchWithDescendantsRequiresForce(t *testing.T) {
+	env := NewTestEnv(t)
+	env.MustRun("init")
+
+	env.MustRun("create", "feat-a")
+	env.CreateCommit("feat-a work")
+	env.MustRun("create", "feat-b")
+	env.CreateCommit("feat-b work")
+
+	env.Git("config", "branch.feat-a.stackParent", "missing-branch")
+
+	result := env.Run("orphan", "feat-a")
+	if result.Success() {
+		t.Fatal("expected orphan of disconnected branch with descendants to require --force")
+	}
+	if !result.ContainsStderr("has children") {
+		t.Errorf("expected error about children, got: %s", result.Stderr)
+	}
+	if v := env.GetStackConfig("branch.feat-a.stackParent"); v != "missing-branch" {
+		t.Errorf("expected feat-a stackParent to remain after failed orphan, got %q", v)
+	}
+	if v := env.GetStackConfig("branch.feat-b.stackParent"); v != "feat-a" {
+		t.Errorf("expected feat-b stackParent to remain after failed orphan, got %q", v)
+	}
+
+	env.MustRun("orphan", "--force", "feat-a")
+
+	if v := env.GetStackConfig("branch.feat-a.stackParent"); v != "" {
+		t.Errorf("expected feat-a stackParent cleared after forced orphan, got %q", v)
+	}
+	if v := env.GetStackConfig("branch.feat-b.stackParent"); v != "" {
+		t.Errorf("expected feat-b stackParent cleared after forced orphan, got %q", v)
+	}
+}