It's always interesting to do some detective work on which rarely seen jewellery piece comes from where. I was trying to find the aquamarines that Margaret of Connaught had (at least one is worn by Anne Marie of Greece as a necklace and Lilian had at least one as well) and I stumbled onto something else.
The earrings Madeleine wore at her pre-wedding dinner and later when she was pregnant...
Could these be the earrings that Princess Sibylla is wearing here?
They might have been modernised later but look the same to me. Did Madeleine receive Sibylla's earrings at some point? I couldn't find pics of anyone else wearing the earrings so I guess they were Sibylla's originally or she inherited them from her family.
Margaretha occasionally wears aquamarine earrings (with Margaret's tiara) but they look different.
The necklace Sibylla is wearing in the picture with the earrings and the Connaught tiara is a sapphire necklace and Birgitta inherited it.