A Squib is a non-magical person who is born to at least one magical parent. Squibs are, in essence, 'Wizard-born Muggles. ' They are rare and are looked upon with a degree of disdain by some witches and wizards, particularly pure-bloods.
The common practice with Squibs was to send them off to Muggle schools as children and encourage them to integrate with the Muggle community, which was much kinder than the other practice which involved letting them live in the magical world where they would always be treated as second-class citizens, but not as bad as ...
Some children were revealed as late-bloomers rather than Squibs, such as Neville Longbottom, but for others (such as school caretaker Argus Filch) their magic would simply never materialise, which could be hard to accept.
Squibs would not be able to attend Hogwarts as students. They are often doomed to a rather sad kind of half-life (yes, you should be feeling sorry for Filch), as their parentage often means that they will be exposed to, if not immersed in, the wizarding community, but can never truly join it.
During his first flying lesson, Albus failed to demonstrate his flying skills and was subsequently nicknamed the "Slytherin Squib". Throughout the following three years of school, Albus continued to suffer the burden of his father's legacy and struggled to live up to others' expectations as the son of Harry Potter.
It is unclear as to Lord Voldemort's attitude towards Squibs. He had personally noted throughout his life that he aims to purge Muggle-born wizards and witches for "stealing" magic. However, as Argus Filch was allowed to remain in Hogwarts, it is likely they weren't prosecuted as blood traitors.
Because, if you follow the definition to the letter, if a child has wizarding grandparents, then he IS considered a pure-blood, even if his parents are NOT wizards themselves. That would mean that someone born to two "pure-blood" squibs is a pureblood, even though both parents have no magical affinity.
No professor McGonagall is not Filch's mom. She was married to Elphinstone Urquhart who died later on and they didn't have any children. She did not have a child as mentioned by Harry when he yells out in Cursed child that McGonagall would not understand why he was worried about Albus because she never had a child.
However, like in the real world, some magical members of certain families or groups have biases toward those who do not conform to a "pure-blood" status, such as being Muggle-born, a Squib or, in the case of Rubeus Hagrid, a half-breed. This prejudice may have affected the Hagrid family in a myriad of ways, but Mr.
Hagrid was a pupil at Hogwarts himself and was learning magic along with everyone else - until one horrible day in his third year, when he was expelled (for reasons we discover later on in the series). Although he was able to stay on as gamekeeper, his wand was snapped in half.
Born to a Muggle mother and a Squib father, Lockhart was the only one among his siblings to possess magical abilities. He attended Hogwarts School of Witchcraft and Wizardry, where he was sorted into Ravenclaw House.
Harry describes Umbridge to Sirius Black, saying that she's vile enough to be a Death Eater, despite not being one. Umbridge is also depicted to be a prejudiced person, despising half-breeds and Muggle-born witches and wizards to the point of firing Hagrid due to his half-giant birth status.
Family. Snape's family background is mostly shown in flashbacks during the course of the last three novels. Snape was born to Eileen Prince, a witch, and Tobias Snape, a Muggle, making him a half-blood (hence the name, "Half-Blood Prince").
Early life. Dolores Umbridge was the first child of a wizard named Orford Umbridge and a Muggle named Ellen Cracknell. Her younger brother was a Squib, but Dolores was a witch.
Later in the year, McGonagall duelled with Death Eater Alecto Carrow during the Battle in the Astronomy Tower and later learned of Snape's murder of Dumbledore. McGonagall was initially appointed as Headmistress, but was demoted after Voldemort took control of the school and placed Snape as Headmaster.
Professor Marazion succeeded Minerva McGonagall in the post of Head of Hogwarts School of Witchcraft and Wizardry. This individual became Headmaster or Headmistress some time between 2008 and 2017 after Minerva McGonagall went into retirement as she was "getting on a bit".
The children of Harry and Ginny Potter were considered half-bloods because although Ginny was pure-blood, Harry's mother was Muggle-born. The term was used as an insult from members of fanatical pure-blood families.
What if a Muggleborn has a child with a Muggleborn?
If Two Muggle-Borns had A Child, Would They Be A Muggle-Born, or a Pureblood or a Halfblood? Yeah, the blood-status is actually not really about the genes. If you are magic, you are magic, there's no in-between.
Witches and wizards with non-magical parents are called Muggle-borns. There have also been some children known to have been born to one magical and one non-magical parent. People of this mixed parentage are called half-bloods; magical people with any Muggle ancestry on the one side or the other are half-bloods as well.
As Dolores Umbridge was a sadist who enjoyed torturing students, Filch could relate to this. Also, as Umbridge granted Filch permission to torture misbehaving students, whereas Dumbledore would never even think of such things, he had loyalty to her. He is the only person who liked her at the school.
The pure-blood wizards and witches featured in the Harry Potter books are almost all supremacists, while there are some of them who do not advocate ancestral superiority; the Potters, Weasleys, and Longbottoms are old pure-blood families, but no known members of these families are sympathetic to supremacist aims.
After Voldemort's defeat by Harry at the Battle of Hogwarts and the restoration of the Ministry of Magic by the new Minister, Kingsley Shacklebolt, Umbridge was sentenced to life imprisonment in Azkaban for her crimes against Muggle-borns.
