diff --git a/changelog/XXXX.fixed.md b/changelog/XXXX.fixed.md
new file mode 100644
index 000000000..8fe264f27
--- /dev/null
+++ b/changelog/XXXX.fixed.md
@@ -0,0 +1 @@
+Added missing `on_dtmf_event` callback to `LemonSliceTransportClient.setup()` `DailyCallbacks` construction, fixing a `ValidationError` at pipeline setup time.
diff --git a/src/pipecat/transports/lemonslice/transport.py b/src/pipecat/transports/lemonslice/transport.py
index 6a6894167..4cdf99ca9 100644
--- a/src/pipecat/transports/lemonslice/transport.py
+++ b/src/pipecat/transports/lemonslice/transport.py
@@ -181,6 +181,7 @@ class LemonSliceTransportClient:
                 on_dialout_stopped=partial(self._on_handle_callback, "on_dialout_stopped"),
                 on_dialout_error=partial(self._on_handle_callback, "on_dialout_error"),
                 on_dialout_warning=partial(self._on_handle_callback, "on_dialout_warning"),
+                on_dtmf_event=partial(self._on_handle_callback, "on_dtmf_event"),
                 on_participant_joined=self._callbacks.on_participant_joined,
                 on_participant_left=self._callbacks.on_participant_left,
                 on_participant_updated=partial(self._on_handle_callback, "on_participant_updated"),