Netgear Orbi WiFi 7 nodes broadcast a Qualcomm vendor IE (8C:FD:F0) in every beacon that contains the parent node's MAC address. I caught a live star-to-daisy-chain reroute and confirmed it against three APIs. Undocumented, not in Wireshark, field map and open questions in the post.

Pretty neat: you can see the whole layout without even being associated to any of the APs!