Tracing Carrie's liniage most consider her to be decended from
Syfa Balnadez whom appeared in Castlevania 3.  The resemblances
are notable.  Both are magic users.  Both have the abillity to fight
vampires.  Not to mention the simillarity of the names.  Balnades
Fernandez.  Well they have a simillarity when you pronounce them anyway.
It at least hints that they stem from the same region.

Let's analyze the bloodline.

We'll start with the Belmonts.
Sonia mother of Trevor.  Most consider that Alucard is
Trevor's father and since the Belmonts are near superhuman in their
strength and agillity it may not be too much of a stretch
to believe that there could be some vampiric attributes.

moving on to Trevor and Sypha.  Since the two were paired up in the
end of Castlevania 3 it's safe to assume Syfa was the one to
help Trevor carry on the Belmont genes.  Of course if this is true
and one assumes Carrie is decended from Syfa then it would make her
a Belmont as well.  So that raises the question.  If Carrie is
decended from Syfa then how did the Fernandez clan seperate from
the Belmonts.

	Theory1-(branching off) there's no reason for Sypha and trevor to only have
one child.  Perhaps the son was as tradition dictates trained as a vampire
hunter while the daughter married off and lost the name and the Belmont tradition
was forgotten.  This could continue untill someone from that line ended up with
the Fernandez clan or perhaps even founded it.

	Theory2-(leaving town) following much like theory 1 only it might have been more
intentional.  Perhaps Syfa thought she should pass on her magic abillities
to one of her children and that child intentionally left the Belmont clan to eventually
intertwine with wandering jypsies and eventually form the Fernandez clan.

	Theory3- (who's the father) Syfa could have been trapped in that
statue for a lot longer than anyone thinks.  It was said she led a rather tragic life
prior to being turned to stone.  It might be possible that she had children before
she was turned to stone and perhaps the father died forcing Syfa to abandon her
child or children.  These possible children might have gone on for generations before
Syfa was re animated by Trevor.

	Theory4- (didn't work out) While Trevor and Syfa were paired at the end of
Castlevania 3, perhaps the relationship didn't work out and they went their seperate ways with
Trevor eventually having children by another woman and Syfa finding another man.
It would explain why no later Belmonts showed any tallent for magic whilst the Fernandez
clan seems quite profficient at it.  Perhaps the father could have been Allucard
or Grant.  Although Grant doesn't much seem like Syfa's type Alucard is considered to be
quite the lady's man as he in most appearances manages to romance the lead female.

	Theory5- (who's the mother) Perhaps simply Carrie isn't decended from
Syfa at all.  Mabey the Fernandez clan stems from the same area and mabey even the same
familly as Syfa but isn't directly decended from her.  But that theory isn't very fun is it.

	Conclusion, 4 out of 5 possibillities say that Carrie is decended from
Syfa, 2 suggest she's decended from Trevor and Syfa and 3 suggest she's decended from
Alucard as well.  So any way you look at it our favorite little ass kicker has genetics on her side.