diff --git a/extensions/org-roam-dailies.el b/extensions/org-roam-dailies.el
index 5d63882..e82d55d 100644
--- a/extensions/org-roam-dailies.el
+++ b/extensions/org-roam-dailies.el
@@ -289,7 +289,7 @@ If FILE is not specified, use the current buffer's file-path."
     (save-match-data
       (and
        (org-roam-file-p path)
-       (file-in-directory-p path directory)))))
+       (org-roam-descendant-of-p path directory)))))
 
 ;;;###autoload
 (defun org-roam-dailies-find-directory ()
diff --git a/org-roam-utils.el b/org-roam-utils.el
index 9d3ccce..8d30de0 100644
--- a/org-roam-utils.el
+++ b/org-roam-utils.el
@@ -108,6 +108,13 @@ SPEC is a list, as per `dolist'."
       `(dolist-with-progress-reporter ,spec ,msg ,@body)
     `(dolist ,spec ,@body)))
 
+;;; File utilities
+(defun org-roam-descendant-of-p (a b)
+  "Return t if A is descendant of B."
+  (unless (equal (file-truename a) (file-truename b))
+    (string-prefix-p (replace-regexp-in-string "^\\([A-Za-z]\\):" 'downcase (expand-file-name b) t t)
+                     (replace-regexp-in-string "^\\([A-Za-z]\\):" 'downcase (expand-file-name a) t t))))
+
 (defmacro org-roam-with-file (file keep-buf-p &rest body)
   "Execute BODY within FILE.
 If FILE is nil, execute BODY in the current buffer.
diff --git a/org-roam.el b/org-roam.el
index 5b7b0f3..d1d75e6 100644
--- a/org-roam.el
+++ b/org-roam.el
@@ -194,7 +194,7 @@ FILE is an Org-roam file if:
        (member ext org-roam-file-extensions)
        (not (and org-roam-file-exclude-regexp
                  (string-match-p org-roam-file-exclude-regexp path)))
-       (file-in-directory-p path (expand-file-name org-roam-directory))))))
+       (org-roam-descendant-of-p path (expand-file-name org-roam-directory))))))
 
 (defun org-roam-list-files ()
   "Return a list of all Org-roam files under `org-roam-directory'.