Someone who is the progeny of a cambion and a mortal (that is, second generation removed from the fiendish parent - the cambion is the first) may be considered still to be cambion, or may be considered to be a tiefling, depending on how strongly they inherit the blood. Cambions are considered true fiends by other fiends, while tieflings are not. The more diluted the blood gets, the fewer fiendish traits surface, however even Cambions are technically able to act outside of the normal LE Devil imperative - this is something that is considered a powerful and useful feature of them as fiends.
We have got some unusual cases of characters who are tieflings only two generations removed from their fiendish parent - I believe that was the case for Valen, in NWN2, but that's the more unusual scenario. Most teiflings in the present day are many, many generations seperated from their fiendish parents, tot eh extent that it can't even really be traced or tracked. The fiendish blood generally stops showing up at all after 1/64 blood dilution, but it never goes away entirely, and tieflings can and do still crop up between completely normal parents if one of them has a non-manifesting trace of that blood legacy.
The Avernus event threw a great big old spanner into this, as I believe it caused everyone with even a trace of fiendish blood at all to spontaneously manifest as teiflings, as well as causing every child conceived or carried during the decent, to be born a tiefling as well. I could be mistaken on those details; I'm not as familiar with the avernus story as I could be.
For other mortal races, technically no; half-orcs and half-elves are, for game mechanical terms written as human other half, but that's not actually necessary, and indeed there are guidelines for determining your racial traits based on what your other half lineage is; it can be any compatible mortal race (there aren't hard and fast rules for that that are 'official'. Even in cases where a race pairing might not be viable for children, it's a world of magic and power; visiting a temple and besearching the appropriate life/fertility deity for a blessing with your normally incompatible partner of choice may absolutely work, if you're lucky, just for example.)
Characters of mixed bloodlines exist all over the realms - as a player, you generally determine what parts of your blood heritage are strongest when selecting what your actual mechanical racial traits should be. So, if you are the child of an elf and an orc, for example, you might take the elven half of the half-elf traits, and then replace the stand-in human other half with the half-orc traits. It's the kind of thing you talk about with your DM when you make the character, though the books do provide guidelines for doing so.
Joke answer: A 'ling' is the Shou language name for pixies.
Just bear in mind that bloodline and blood heritage influence is not just from actual procreation alone, in the realms - storm sorceresses generally don't owe that to their parent getting it off with an air elemental. Other major influences impact these things - planar exposure, divine/demonic intervention, and a number of other things can spontaneously create or influence legacy bloodlines without a particular parent ever having any exotic tastes at all. The avernus events are actually a good example of that - the sudden massive uptick in tiefling births is not because everyone went and slept with devils while they were there - it was more a case of pervasive planar influence affecting them. (Though I've no doubt at all that at least a few were caused in the more traditional way...)
By that point in your lineage your character is what scholars might refer to as a 'Bitsa', or possibly a 'Mutt' ^.^ You can of course define your character as you like, if your dm approves it, though my personal take would ebthat in that situation.. let's see...
So, if I'm reading that right, your father comes out as 1/8 dragon blooded tiefling half-orc with a quarter of orgre blood (we have half-orgres to work from, also half-dragons), while your mother would be a 1/4 nymph-blooded elf.
That would mean that your character could display any number of traits, depending on how the chromosones land, though by this point it sounds like there's a great old one who is eyeing you up as a future warlock for them, with the amount of bloodline fiddling that's been going on ^.^ You might formally have trace bloodline legacies from (1/16) dragon, (1/8) ogre, and (1/8) nymph, but overall; the tiefling ancestry would still be very strong, and would probably stand a god chance of overruling most other trace elements on your father's side - the orcish lineage would also be strong. On your mother's side, the elven ancestry would probably be dominant, just with a mildly more fey than usual cast to it... So for yourself, you might choose to present as tall and fair, but with obvious fiendish presence; your stature and build would likely be reigned in by your mother's side, but you might have the impression of a powerful frame, even if your overall height wasn't excessively more than normal for an elf. You might start from the half-elf base, using the elf side of the half-elf traits, then replace the two human-side traits with one from tiefling and one from half-orc. Visually, your fiendish manifestation might have trace elements that are more reminiscent of draconic scales than devil leather - your horns, if you have them might, coincidentally resemble the horns of the dragon colour you owe that trace of your lineage to. I'd be happy with a player running something like that. ^.^
