diff --git a/src/posts/delete.js b/src/posts/delete.js
index dddb33e6a9..ba637ccff5 100644
--- a/src/posts/delete.js
+++ b/src/posts/delete.js
@@ -197,20 +197,15 @@ module.exports = function (Posts) {
 	}
 
 	async function deleteFromReplies(postData) {
-		const arrayOfReplyPids = await db.getSortedSetsMembers(postData.map(p => `pid:${p.pid}:replies`));
-		const allReplyPids = _.flatten(arrayOfReplyPids);
-		const promises = [
-			db.deleteObjectFields(
-				allReplyPids.map(pid => `post:${pid}`), ['toPid']
-			),
-			db.deleteAll(postData.map(p => `pid:${p.pid}:replies`)),
-		];
+		// Any replies to deleted posts will retain toPid reference (gh#13527)
+		await db.deleteAll(postData.map(p => `pid:${p.pid}:replies`));
 
+		// Remove post(s) from parents' replies zsets
 		const postsWithParents = postData.filter(p => parseInt(p.toPid, 10));
 		const bulkRemove = postsWithParents.map(p => [`pid:${p.toPid}:replies`, p.pid]);
-		promises.push(db.sortedSetRemoveBulk(bulkRemove));
-		await Promise.all(promises);
+		await db.sortedSetRemoveBulk(bulkRemove);
 
+		// Recalculate reply count
 		const parentPids = _.uniq(postsWithParents.map(p => p.toPid));
 		const counts = await db.sortedSetsCard(parentPids.map(pid => `pid:${pid}:replies`));
 		await db.setObjectBulk(parentPids.map((pid, index) => [`post:${pid}`, { replies: counts[index] }]));
diff --git a/src/topics/posts.js b/src/topics/posts.js
index 8201bcad02..41b819d219 100644
--- a/src/topics/posts.js
+++ b/src/topics/posts.js
@@ -184,6 +184,9 @@ module.exports = function (Topics) {
 			.filter(p => p && p.hasOwnProperty('toPid') && (activitypub.helpers.isUri(p.toPid) || utils.isNumber(p.toPid)))
 			.map(postObj => postObj.toPid);
 
+		const exists = await posts.exists(parentPids);
+		parentPids = parentPids.filter((_, idx) => exists[idx]);
+
 		if (!parentPids.length) {
 			return;
 		}