Trevor

Trevor was Neville Longbottom's pet toad. He was given to Neville by his Great-Uncle Algie upon Neville's gaining admission to Hogwarts School of Witchcraft and Wizardry.

1991-1992
Neville lost Trevor many times. For example, the first time he came to Hogwarts on the Hogwarts Express, Neville lost Trevor but was soon helped by Hermione Granger who met Harry Potter and Ron Weasley during her search.

Professor Flitwick once made Trevor fly around his Charms classroom to skillfully demonstrate levitation spells.

1993-1994
In Neville's third year, Trevor was part of the Frog Choir when they performed Something Wicked This Way Comes on 1 September. Later on the school year, Professor Snape made him test his Shrinking Solution on the toad, with the warning that if made incorrectly, it would likely be poisonous. After Trevor drank the potion he successfully transformed into a tadpole, much to the Gryffindor's delight; however, Professor Snape was displeased and deducted five points from Gryffindor because Hermione had helped Neville create the potion.

1994-1995
Harry used Trevor to practice the Summoning Charm in his and Neville's fourth year.

1995-1996
When Harry encountered Neville in the last carriage of the Hogwarts Express in their fifth year, Neville had a one-handed grip on a struggling Trevor. Later, Neville dumped the toad into Harry's lap, so that he could demonstrate the defencive mechanism of his Mimbulus Mimbletonia. This was to Harry's regret when Cho Chang then visited the compartment, as "he would not have chosen to be sitting with Neville and Loony Lovegood, clutching a toad and dripping in Stinksap."

1996-1997
Trevor made a bid for freedom on the Hogwarts Express, but Neville caught him again.

Later life
At some point, Trevor escaped into the Lake. Both pet and owner felt a sense of relief.

Behind the scenes

 * There was a theory by a fan named Naomi that Trevor was the Animagus form of Neville's Uncle Algie, but this was said to be false by Rowling.
 * In the Spanish translations of the books Trevor has been tranferred into a turtle instead of a toad.

Appearances

 * Harry Potter and the Philosopher's Stone
 * Harry Potter and the Philosopher's Stone (film)
 * Harry Potter and the Philosopher's Stone (video game)
 * Harry Potter and the Prisoner of Azkaban
 * Harry Potter and the Prisoner of Azkaban (film)
 * Harry Potter and the Prisoner of Azkaban (video game)
 * Harry Potter and the Goblet of Fire
 * Harry Potter and the Order of the Phoenix
 * Harry Potter and the Order of the Phoenix (video game)
 * Harry Potter and the Half-Blood Prince
 * Harry Potter and the Half-Blood Prince (film)
 * LEGO Harry Potter: Years 1-4
 * LEGO Harry Potter: Years 5-7
 * Pottermore
 * Harry Potter Trading Card Game