Out of curiosity, is it possible to have two familiars?
As far as I know there are two possible ways to obtain familiars. One is with the find familiar spell; the other is to find a creature with the familiar variant option.
In the first instance, the rules specify that you can't have more than one familiar, but the way is worded seems to be referring to the find familiar spell:
You gain the service of a familiar, a spirit that takes an animal form you choose.
The familiar has the statistics of the chosen form, though it is a celestial, fey, or fiend (your choice) instead of a beast.
You can’t have more than one familiar at a time. If you cast this spell while you already have a familiar, you instead cause it to adopt a new form.
But in the variant case you don't have a spirit per-se; you have the actual living thing and it does not change forms (as in the spell). Also, there is nothing in the variant rules that seems to rule out the option of having two familiars:
Variant: Quasit Familiar
[...]
The quasit can serve another creature as a familiar, forming a telepathic bond with its willing master. While the two are bonded, the master can sense what the quasit senses as long as they are within 1 mile of each other. While the quasit is within 10 feet of its master, the master shares the quasit's Magic Resistance trait. At any time and for any reason, the quasit can end its service as a familiar, ending the telepathic bond.
And, as far as I know, there is no limit on how many telepathic bonds you may have, if the telepathic communication and "possession" is considered a telepathic bond.
Therefore, is it really possible to have two familiars, particularly using both rules, the find familiar and the variant option, or I missing something?