I believe there have been discussions on whether Squibs can have wizard offspring. Assuming that two Squibs can produce wizard offspring, what blood status would that offspring have? Perhaps if the Squibs were half-bloods themselves, the offspring would be half-blood; what if the Squibs were from pureblood families? Would they be Muggle-born, if Squibs are Muggles? Would they be Purebloods, if Squibs are still counted as sort-of-wizards? Would they be half-bloods, if it's somewhere in between?
This depends on who defines blood status.
Many blood status fanatics saw squibs "politically"/"bigot-wise" to be the same as Muggles (this was discussed in detail in Beedle the Bard).
However, Voldemort regime in Year 7 of HP books went with the official Nazi-based definition (see this answer for details) which would technically make a pureblood-born Squib pureblood, and therefore a child of 2 such, a pureblood.
Keyword here being "technically" - see the last 2 paragraphs of the linked answer, or here as well.
- As a side note, to prove that you're pure-blood, you need to (see the trials shown in HP7) prove your bloodline. Many pureblood parents would probably disown Squib kids and not want to acknowledge the truth, especially during HP7 times, therefore, someone who may have technically been a pureblood biologically would possibly have a hard time proving that purebloodedness legally.
OTOH, most Squibs would live among Muggles (e.g. see comments here for reference), and many would be "blood traitors" despite that "technically pureblood" status.
It would definitely depend on the Squibs bloodlines, but couldn't we just make it a lot easier by calling the produce a Squib-born. Wizards aren't known for their logic ^^ proof of this fact is that we're talking about blood status, so calling a magical child of two squibs a squib-born to them would be 'the ultimate insult' by the extremists, and 'completely correct' by the blood traitors, muggleborns and halfbloods.