I like the idea of this connection. It would make since if the BF banished Tink to NL due to her relationship with Belle’s father. Also, it would explain why the BF is so against fairies being in love. Their has to be a reason behind this and I believe the BF said it distracts them from their duty. So maybe Tink was to guide Maurice and fell in love with him instead, had Belle and something horrible happened as a result. His kingdom and people fell prey to disaster.
Those are excellent thoughts which tie a lot of loose ends together about Belle’s hitherto untold family history. (Now, I’ll be disappointed if this theory turns out to be wrong). I think you’re right about Blue opposing romances for fairies (either from Blue’s own personal experience or from the disastrous love affair of another fairy such as Tink). I recall in “Dreamy” how the BF opposed Nova falling in love because it would thwart her becoming a fairy-godmother. Well, perhaps Tink was being groomed to be fairy god-mother to Sir Maurice’s family but instead they had a love affair. Perhaps whatever protective magic lay over his family was lifted when Blue banished Tink to NL and so his house fell into ruin and despair, leaving his kingdom open to attack by the ogres (which we all know led to Rumple taking Bell as his captive in Skin Deep).
It would also explain why Belle is able to do the spell to protect SB, she has magic within her.
It would make a lot of sense that Belle could cast a cloaking spell because she is half-fae! Also, it’d be quite ironic if the Dark One were in love with the daughter of a fairy.
"That’s how you know you’ve really got a home. When you leave it, there’s this feeling that you can’t shake. You just miss it." Neal Cassidy