Short answer: almost certainly nonexistant.
To examine the issues in order:
The chance that any Garou will have a child with any of the above is pretty much zero.
Garou have extreme difficulty reproducing, so most are very picky about the non-Garou parents of their offspring - they're looking for maximum chance of another Garou. Almost all Garou reproduction occurs with Kinfolk - who cannot be revenants, are unlikely to become ghouls (since Garou would intervene to protect or kill them), and are unlikely to be sired by even the most reckless 14th-gen vampire.
If we assume the parent is not Kin, they'd still have to get their ghoul or vampire nature past a Garou's enhanced senses. (Even a Garou willing to have sex with a ghoul is pretty unlikely to risk having children with one.)
So it's going to require an unlikely and contrived set of circumstances to make this happen.
But love breaks all bounds, and human recklessness more so. Unlikely and contrived sets of circumstances are what GMs are for, so let's assume it somehow happens...
The child is probably a normal human. With an extremely screwed up family life.
Children of ghouls are, pretty much, children - although if the ghoul is old enough and blood-steeped enough, especially if past natural childbearing age, the child might be born already a ghoul. (Note that a ghoul this old is a valued retainer, extremely unlikely to end up mating with a Garou without it's master's knowledge. Remember, the ghoul is Blood Bound - which means the ghoul's master certainly knows about the child. A Garou is very unlikely to miss, or stand for, that situation for long.)
Children of Garou are either Kin or Garou.
If Kin, they're a normal human and will react as would any ghoul child - except for the much greater chance of attracting Garou attention at some point.
And if, by a wild chance, they're Garou...
...then they're a Garou. In an unusually messed up family situation, even by the generous standards of Garou. (I'm assuming here that the Garou parent somehow missed knowing about the ghoul parent's background, or their Kindred patron. If they didn't... they're likely to kill the ghoul parent and take or kill the child. Or die trying.)
Since Garou tend to be absentee parents - more so in this case, since this scenario is most likely if the Garou parent died - the child will live much like any child of a ghoul for the first decade or so. (Except that they'll be unusually upset by early attempts to ghoul them; vitae will taste and seem horribly wrong to them, as it does to Garou.)
And at puberty... if they've been left alone, they'll change as normal.
And if they've been ghouled... then you'll get an unusually strong, unusually confused, vitae-addicted, Rage-prone Garou teenager. The Blood Bond might offer a means to control them, but it's not likely to protect against Rage-fuelled teenage mood swings, much less uncontrolled changes.
If the ghoul parent (and their Kindred patron) were unaware of the Garou parent's origin, this is likely to come as a terminal shock to all concerned. Including the Garou parent, when they come back to check on their child. (Many Garou will consider their having a child with a ghoul, much less Cainite, as a serious violation of "Combat the Wyrm Wherever it Dwells and Whenever it Breeds". They're not likely to be kind to the child either.)
