diff --git a/live/operator-session/clawdie-enable-mother.sh b/live/operator-session/clawdie-enable-mother.sh
index a53d83fa..ed29bcd1 100755
--- a/live/operator-session/clawdie-enable-mother.sh
+++ b/live/operator-session/clawdie-enable-mother.sh
@@ -62,17 +62,26 @@ mdo -u root sh -c '
     fi
 ' sh "$COLIBRI_HOME" "$SSH_KEY"
 
-# 3. Write the mother entry into the external MCP registry.
+# 3. Merge the mother entry into the external MCP registry. Use jq so existing
+# server entries are preserved (not overwritten), and write atomically.
 echo "[2/4] Registering mother in ${EXTERNAL_MCP}..."
-printf '%s\n' "{
-  \"servers\": {
-    \"mother\": {
-      \"command\": \"ssh\",
-      \"args\": [\"-i\", \"${SSH_KEY}\", \"-o\", \"BatchMode=yes\", \"-o\", \"StrictHostKeyChecking=accept-new\", \"${MOTHER_HOST}\", \"${MOTHER_CMD}\"],
-      \"env\": {}
-    }
-  }
-}" | mdo -u root sh -c 'cat > "$1"; chmod 0644 "$1"' sh "$EXTERNAL_MCP"
+if ! have jq; then
+    echo "       ERROR: jq is required to merge the mother entry into ${EXTERNAL_MCP}."
+    finish 1
+fi
+existing="$(mdo -u root cat "$EXTERNAL_MCP" 2>/dev/null || echo '{}')"
+[ -n "$existing" ] || existing='{}'
+printf '%s\n' "$existing" |
+    jq --arg host "$MOTHER_HOST" --arg cmd "$MOTHER_CMD" --arg key "$SSH_KEY" \
+        '.servers = ((.servers // {}) + {mother: {command: "ssh", args: ["-i", $key, "-o", "BatchMode=yes", "-o", "StrictHostKeyChecking=accept-new", $host, $cmd], env: {}}})' |
+    mdo -u root sh -c '
+        set -eu
+        f="$1"
+        tmp="$(mktemp "$(dirname "$f")/external-mcp.XXXXXX")"
+        cat >"$tmp"
+        chmod 0644 "$tmp"
+        mv "$tmp" "$f"
+    ' sh "$EXTERNAL_MCP"
 
 # 4. Allow external MCP calls: upsert COLIBRI_MCP_EXTERNAL_CALL=1 into provider.env.
 echo "[3/4] Enabling external MCP calls..."