Her family is from Paraná, Brazil, where her mother, 71, and father, 76, live.
Alexandre said he was particularly worried about his mother, who was struggling to eat and sleep as the family waited thousands of kilometres away for news.
Police and family remain concerned for the welfare of missing woman Erika Rodrigues Coelho.
The family learned Erika was missing about a week after her disappearance, when her best friend Bruna Rech contacted their mother, he said.
They have since relied on Rech, Erika’s partner and news reports for information about the search.
Alexandre described his sister as dedicated, truthful, authentic and deeply private.
The family was still hoping she could be sheltering somewhere, such as a hut, and would be found safe.
They had discussed travelling to New Zealand but were waiting for search developments before deciding what to do.
Rech, a dentist living in North Carolina, met Erika when they worked at the same hospital in Florianopolis, Brazil, in 2021.
They remained close despite the distance, speaking every few days.
Rech said her friend was passionate about sport, including running, cycling and hiking. She had completed a marathon and several half-marathons.
Erika Rodrigues Coelho running in Florianopolis, Brazil.
The friends last spoke on September 16.
“It was a normal, friendly conversation about our lives,” Rech said.
She said Erika had not mentioned plans to go hiking.
Rech messaged Erika again on September 19 but received no reply.
The following day, Erika’s partner contacted her saying he was concerned because she had not turned up for work and he had not seen her since Thursday, Rech said.
“Erika is extremely organised, so when he told me she hadn’t shown up for work I was immediately alarmed.”
Rech began trying to contact her friend and said her messages were delivered but went unanswered.
She also contacted the Brazilian Embassy and has since been in direct contact with New Zealand police.
The Brazilian Embassy in Wellington told the Herald it has been following the case from the beginning and is in contact with both Erika’s family and police in Queenstown.
Rech said Erika had confided in her before her disappearance that she had been feeling sad about personal matters.
Despite anxiety and sleepless nights since her friend disappeared, Rech said she remained hopeful.
“Erika is a very strong woman. She has always been very strong”
Erika had previously been reported missing in January after leaving Queenstown and travelling to the Mārahau area in Nelson Tasman.
Police sought public help to find her before confirming she had been located the following day.
Rech said that occasion was different from her current disappearance because Erika had chosen to go on a long hike and was safe.
“I thought, maybe she was on another long hike, like last time. But then seven days had passed. The time for the hike had passed, and the rental car period had passed too.”
In Queenstown, Erika’s next-door neighbour Jihane Sato also knew her through LSNZ, the English language school Erika attended for about a year after arriving in New Zealand in 2024.
Sato said Erika had come to New Zealand to improve her English and hoped eventually to have her medical qualifications recognised and return to her profession.
She was most recently working in retail and living in Shotover with her Kiwi partner.
Sato described her as a “very private” person who did not have a large social circle, but said she had always appeared happy.
She last saw Erika walking in their neighbourhood during the week she disappeared.
“The Brazilian community is really worried about her, especially the teachers who taught her when she was studying English. Everyone is very concerned for her,” Sato said.
Police were notified on September 20 and launched a search involving Land Search and Rescue volunteers, Coastguard Queenstown, drones, search dogs, a helicopter and ground teams.
Search and rescue teams are continuing to look for missing Queenstown woman Erika Rodrigues Coelho.
Erika’s rental Toyota RAV4 was found at Skippers Saddle near Coronet Peak on September 21.
Police are now seeking a man seen on the Mt Dewar summit track about 12.30pm on September 18 who may have useful information to the investigation.
Police say he may be a tourist and have urged him, or anyone who can identify him, to come forward.
Anyone with information is asked to contact police on 105, quoting reference 260921/8173.
Information can also be provided anonymously to Crime Stoppers on 0800 555 111.
Rafaella Melo is a multimedia journalist with more than 10 years’ experience in Brazil. She spent two years reporting for Hawke’s Bay Today before joining the NZ Herald’s Christchurch team in 2026.