Above is the Coat of Arms of Mr Michael Middleton, father of HRH The Duchess of Cambridge. This shows, for the first time to my knowledge, the crest. A crest isn't the whole Coat of Arms it is just the part which sits on a helmet, only in this case there isn't a helmet.
Between helmet and crest is what is called a Torse. This is a twist of material which served the dual purpose of masking the join between helm and crest, and holding the Mantling in place. In this case the colours don't exactly reflect the main colours of the Shield but are a more patriotic red, white and blue, instead of red, gold and blue.
The Crest itself seems to show a blue Wolf sitting sideways on a rock and holding a Rod of Caduceus (two Snakes wound round a winged Staff). This is not to be confused with a Rod of Asclepius which only has one Snake and represents medicine. It is unknown what the Rod of Caduceus represents here.
What seems to be the consensus as far as The Duchess of Sussex's Coat of Arms is concerned is that it will be granted directly to Her Royal Highness. There is a precedent, namely HRH The Duchess of Gloucester, whose parents were also divorced.
The bird is a Lapwing and features in the heraldry of the Danish Family Van Deurs, i.e. her Mother's side. The Blazon for which appears to be Azure a Lapwing Argent standing on soil Vert. In other words, a white/silver Lapwing standing on green ground against a blue background. HRH's Lapwing is in its natural colours rather than silver and the green ground has been replaced by crossed black Ostrich Feathers on a yellow/gold Chief at the top of the Shield.
We shall have to wait and see...