Moomintroll is romantically in love with Snufkin.Noticeable mostly in the books Finn Family Moomintroll and Moominsummer Madness. This has been pointed out in everything from fangirl musings to actual creditable academic essays, and is supported by Snufkin being modeled after Tove Janssons one-time fiancÚ Atos Wirtanen, while Moomintroll often acts as a placeholder for herself, as well as her known LGBT tendencies. While this is never actually pointed out directly in the original novels, it is heavily implied and is accepted as pretty much canon in a lot of people's opinion.
Sniff is Fillyjonk.Either one of them, or everyone at the same time. Notice how similar the shape of their heads are, they are basically the same. Sniff could easily bend back his ears and hide them under a wig or a particularly pointy hat. Also note how none of the fillyjonks ever show any skin lower than the neck. There are no visible female shapes and Sniff's anatomy could very well be hidden under a long dress. And while their personalities aren't exactly the same, they are at least in the same general area. Most peculiar, however, is how the fillyjonks are introduced in the book right after the one where Sniff makes his last regular appearance. Sniff makes a few brief appearances after that, but only once in the same story as a fillyjonk. In other words, apart from one exception, they never appear at the same time.
Too-ticky is a whomper.Pretty much every character in Moominvalley is described as belonging to a species (I.E., Moomintrolls, Snorks, Hemulens, Mymbles, etc.) where the exceptions at least has a similar relative. Too-ticky, however, is never described as either human or any other species, neither does she have any relative or other counterparts. Keeping all the different species, races and families in mind, Too-ticky resembles the whompses the most. They are both human-like with wild and shaggy hairstyles, a lot of the whompses (presumably children) are also a bit short and chubby. Furthermore, there's is a shared fondness of the sea, implied by the picture book Who will comfort Toffle?, where the whompses are also at parts depicted with striped or patterned sweatshirts and tuft hats, just like Too-ticky.
The return of the family at the end of Moominvalley in November is just one of Toft's wild fantasies.Throughout the book, Toft constantly has vivid imaginations and fantasies. The very reason he comes to the Moominvalley is because he has trouble imagining it at the beginning, but finds upon arrival that it's not like he had dreamed, with the family absent. Throughout the rest of the book, he picks up reading and imagines what he finds in the book so vividly that it frightens him. At the end, when everyone has left the valley after having fulfilled their needs, Toft is the only one remaining. At this point he finds that his dreams about the family and the valley has grown so much that they tire and overwhelm him, and he has difficulties telling reality from fantasy. After a trip through an ungracious forest where his romanticized view of Moominmamma is brought down to earth, he ends up on a hillside overlooking the sea. Towards the evening he sees the light from a boat, and walks down to the beach to welcome the family. This could just as well be a fantasy, a dream in Toft's sleep or perhaps just any other boat. The fact that this is the end of the last of the Moomin novels, where the last ones was mainly about deconstructing the family, and the concept of it, ending up with the last part which is all about the absence of it, strongly suggests that this ending is just a naive dream, ignoring the reality that the Moomin family is forever gone.
The King's Ruby is a symbol of love.With Thingumy and Bob based upon Tove Jansson herself and her secret love Vivica Bandler, it's heavily implied that the two characters are secretly in love with each others. If you take the King's Ruby as a symbol of this love, it makes a lot of sense. Thingumy and Bob arrive in the valley bringing a mysterious suitcase with a hidden content no one can see, shortly afterwards always lonely Groke arrives, wanting the stolen contents of the suitcase brought back to her. In the court case held by the Snork, Thingumy and Bob state that the contents of the suitcase is the most beautiful thing in the world, while the Groke thinks it's the most valuable. Later on, Thingumy and Bob use the ruby to cheer up Moomintroll after Snufkin has left, as well as showing it of to the rest of the valley as a form of gratitude. The Hobgoblin arrives demanding the ruby, which Thingumy and Bob denies him. It's not until the Hobgoblin has showed kindness by fulfilling the wishes of the valleys inhabitants that they wish for an identical ruby for the Hobgoblin, which makes him incredibly happy.
The family are called the Moomins because the orphanage hemulen had no fantasy.Seeing as how Moominpappa was an orphan, his background is shrouded in mystery. Seeing as the hemulen taking care of the moomintrolls of the orphanage knew nothing about childhood wonders or fantasies, it's no stretch to say she had very little imagination. This makes it likely that she just named the orphan "Moomintroll", or perhaps just "Moomintroll #13", because she couldn't come up with anything else. This then carried on into adulthood, where it was taken as a family name.
Snufkin is a terrorist.What with attacking the Park Keeper with hattifatteners, making him glow in the dark and scare him off his own property, while kidnapping the 24 orphans and removing all the signs in the park, which led to him being chased down by police and brought to justice, Snufkin is by all definitions of the word a terrorist in the eyes of the law. Led only by an ideological agenda, one can only guess at how much chaos and destruction he creates on his travels.