diff --git a/electrum/lnchannel.py b/electrum/lnchannel.py
index 5458a2b0c..5329dd271 100644
--- a/electrum/lnchannel.py
+++ b/electrum/lnchannel.py
@@ -230,6 +230,29 @@ class AbstractChannel(Logger, ABC):
     def is_redeemed(self):
         return self.get_state() == ChannelState.REDEEMED
 
+    def need_to_subscribe(self) -> bool:
+        """Whether lnwatcher/synchronizer need to be watching this channel."""
+        if not self.is_redeemed():
+            return True
+        # Chan already deeply closed. Still, if some txs are missing, we should sub.
+        # check we have funding tx
+        # note: tx might not be directly related to the wallet, e.g. chan opened by remote
+        if (funding_item := self.get_funding_height()) is None:
+            return True
+        if self.lnworker:
+            funding_txid, funding_height, funding_timestamp = funding_item
+            if self.lnworker.wallet.adb.get_transaction(funding_txid) is None:
+                return True
+        # check we have closing tx
+        # note: tx might not be directly related to the wallet, e.g. local-fclose
+        if (closing_item := self.get_closing_height()) is None:
+            return True
+        if self.lnworker:
+            closing_txid, closing_height, closing_timestamp = closing_item
+            if self.lnworker.wallet.adb.get_transaction(closing_txid) is None:
+                return True
+        return False
+
     @abstractmethod
     def get_close_options(self) -> Sequence[ChanCloseOption]:
         pass
diff --git a/electrum/lnworker.py b/electrum/lnworker.py
index 5f6a579c2..5ecaaabb7 100644
--- a/electrum/lnworker.py
+++ b/electrum/lnworker.py
@@ -762,10 +762,10 @@ class LNWallet(LNWorker):
         self.lnrater = LNRater(self, network)
 
         for chan in self.channels.values():
-            if not chan.is_redeemed():
+            if chan.need_to_subscribe():
                 self.lnwatcher.add_channel(chan.funding_outpoint.to_str(), chan.get_funding_address())
         for cb in self.channel_backups.values():
-            if not cb.is_redeemed():
+            if cb.need_to_subscribe():
                 self.lnwatcher.add_channel(cb.funding_outpoint.to_str(), cb.get_funding_address())
 
         for coro in [
diff --git a/electrum/wallet.py b/electrum/wallet.py
index 0c112f551..a82d43375 100644
--- a/electrum/wallet.py
+++ b/electrum/wallet.py
@@ -878,6 +878,7 @@ class Abstract_Wallet(ABC, Logger, EventListener):
             result = {}
             parents = []
             tx = self.adb.get_transaction(txid)
+            assert tx, f"cannot find {txid} in db"
             for i, txin in enumerate(tx.inputs()):
                 _txid = txin.prevout.txid.hex()
                 parents.append(_txid)