On 13 July, the Franks were joined by the van Pels family: Hermann, Auguste, and 16-year-old Peter, and then in November by Fritz Pfeffer, a dentist and friend of the family. Anne wrote of her pleasure at having new people to talk to, but tensions quickly developed within the group forced to live in such confined conditions. After sharing her room with Pfeffer, she found him to be insufferable and resented his intrusion, and she clashed with Auguste van Pels, whom she regarded as foolish. She regarded Hermann van Pels and Fritz Pfeffer as selfish, particularly in regards to the amount of food they consumed. Some time later, after first dismissing the shy and awkward Peter van Pels, she recognised a kinship with him and the two entered a romance. She received her first kiss from him, but her infatuation with him began to wane as she questioned whether her feelings for him were genuine, or resulted from their shared confinement. Anne Frank formed a close bond with each of the helpers and Otto Frank later recalled that she had anticipated their daily visits with impatient enthusiasm. He observed that Anne's closest friendship was with Bep Voskuijl, "the young typist... the two of them often stood whispering in the corner."
During the first half of July, Anne and her family went into hiding in an apartment which would eventually hide four Dutch Jews as well -- Hermann, Auguste, and Peter van Pels, and Fritz Pfeffer. For two years, they lived in a secret attic apartment behind the office of the family-owned business at 263 Prinsengracht Street, which Anne referred to in her diary as the Secret Annex. Otto Frank's friends and colleagues, Johannes Kleiman, Victor Kugler, Jan Gies, and Miep Gies, had previously helped to prepare the hiding place and smuggled food and clothing to the Franks at great risk to their own lives. On August 4, 1944, the Gestapo (German Secret State Police) discovered the hiding place after being tipped off by an anonymous Dutch caller.