diff --git a/akka-cluster/src/main/scala/akka/cluster/MembershipState.scala b/akka-cluster/src/main/scala/akka/cluster/MembershipState.scala
index 6c4a326d42..d2443066fb 100644
--- a/akka-cluster/src/main/scala/akka/cluster/MembershipState.scala
+++ b/akka-cluster/src/main/scala/akka/cluster/MembershipState.scala
@@ -60,14 +60,18 @@ import akka.util.ccompat._
       !members.exists(member => member.dataCenter == selfDc && convergenceMemberStatus(member.status))
 
     // If another member in the data center that is UP or LEAVING and has not seen this gossip or is exiting
-    // convergence cannot be reached. For the first member in a secondary DC all members must have seen
-    // the gossip state.
-    def memberHinderingConvergenceExists =
+    // convergence cannot be reached. For the first member in a secondary DC all Joining, WeaklyUp, Up or Leaving
+    // members must have seen the gossip state. The reason for the stronger requirement for a first member in a
+    // secondary DC is that first member should only be moved to Up once to ensure that the first upNumber is
+    // only assigned once.
+    def memberHinderingConvergenceExists = {
+      val memberStatus = if (firstMemberInDc) convergenceMemberStatus + Joining + WeaklyUp else convergenceMemberStatus
       members.exists(
         member =>
           (firstMemberInDc || member.dataCenter == selfDc) &&
-          convergenceMemberStatus(member.status) &&
+          memberStatus(member.status) &&
           !(latestGossip.seenByNode(member.uniqueAddress) || exitingConfirmed(member.uniqueAddress)))
+    }
 
     // Find cluster members in the data center that are unreachable from other members of the data center
     // excluding observations from members outside of the data center, that have status DOWN or is passed in as confirmed exiting.
diff --git a/akka-cluster/src/test/scala/akka/cluster/GossipSpec.scala b/akka-cluster/src/test/scala/akka/cluster/GossipSpec.scala
index c57ec39849..01213ce250 100644
--- a/akka-cluster/src/test/scala/akka/cluster/GossipSpec.scala
+++ b/akka-cluster/src/test/scala/akka/cluster/GossipSpec.scala
@@ -28,6 +28,7 @@ class GossipSpec extends AnyWordSpec with Matchers {
   val e1 = TestMember(Address("akka", "sys", "e", 2552), Joining)
   val e2 = TestMember(e1.address, Up)
   val e3 = TestMember(e1.address, Down)
+  val f1 = TestMember(Address("akka", "sys", "f", 2552), Joining)
 
   val dc1a1 = TestMember(Address("akka", "sys", "a", 2552), Up, Set.empty, dataCenter = "dc1")
   val dc1b1 = TestMember(Address("akka", "sys", "b", 2552), Up, Set.empty, dataCenter = "dc1")
@@ -272,6 +273,24 @@ class GossipSpec extends AnyWordSpec with Matchers {
       state(g2, dc2e1).convergence(Set.empty) should ===(true)
     }
 
+    "not reach convergence for first member of other data center until all have seen the gossip 2" in {
+      // reproducer test for issue #29486
+      val dc2e1 = TestMember(e1.address, status = Joining, roles = Set.empty, dataCenter = "dc2")
+      val dc2f1 = TestMember(f1.address, status = Joining, roles = Set.empty, dataCenter = "dc2")
+      val g =
+        Gossip(members = SortedSet(dc1a1, dc1b1, dc2e1, dc2f1))
+          .seen(dc1a1.uniqueAddress)
+          .seen(dc1b1.uniqueAddress)
+          .seen(dc2f1.uniqueAddress)
+
+      // dc2 hasn't reached convergence because dc2e1 has not seen it (and that matters even though it is only Joining)
+      state(g, dc2f1).convergence(Set.empty) should ===(false)
+
+      // until all have seen it
+      val g2 = g.seen(dc2e1.uniqueAddress)
+      state(g2, dc2f1).convergence(Set.empty) should ===(true)
+    }
+
     "reach convergence per data center even if another data center contains unreachable" in {
       val r1 = Reachability.empty.unreachable(dc2c1.uniqueAddress, dc2d1.uniqueAddress)