Abuja, Nigeria (CNN)Esther Yakubu gazes longingly at the familiar grainy photograph of her daughter and sings a favorite tune as she thinks of her.
Chibok girl's parents react to first glimpse of daughter in two years
But two long years after Maida and more than 200 of her classmates were kidnapped by Boko Haram, another image is now foremost in her mind: that of the teenager at gunpoint, pleading for her freedom.
"Seeing my baby standing with a terror[ist] with ... ammunition around his neck is not easy for a mother," says Esther. "But I also give thanks to God almighty. They say most of the girls are dead but mine is alive."
Maida's captors used her as an unwilling spokeswoman in a new video showing some 50 of the Chibok girls -- alongside graphic, grisly video scenes showing the lifeless bodies of young women, taken in the aftermath of what the terror group says was a Nigerian airstrike.
Wearing a faded black abaya and patterned headscarf, the 18-year-old looks down as a camouflage-clad militant armed with a gun instructs her to speak.
In contrast to the screensaver on Esther's phone, which shows Maida as a bright 16-year-old in her Sunday best, her life stretching out before her, in the new footage there is no happy grin, and Maida's future is decidedly uncertain.
Hesitantly, she explains who she is, and where she is from, before issuing a scripted plea for freedom.
Behind her, fellow hostages in floor-length robes watch, stone-faced, as she urges their parents to press the Nigerian government to free terrorist fighters in exchange for their release.
For Esther and her husband Yakubu Kabu the clip, released by Boko Haram on Sunday, is the first proof that Maida is alive since she was taken from her school in April 2014.
"When I saw that video, I am very sad because this is my baby standing there with someone holding a gun," says Yakubu. "All of us we start crying.
"I give God the glory that she's alive. This video gives us hope that our daughter can be rescued."
Maida, named after her aunt, grew up as one of five children (two boys and three girls) born to the couple, a driver and a local government worker.
A hardworking student, she was known as Dorcas at school (like many Nigerians, the family has both native and English names), and had been looking forward to her graduation; the photo on her mother's phone was taken for a calendar planned to mark the occasion.
Her family says she was keen to continue her education, and hoped to become a lecturer.
"I promised her that I will try my utmost best to say that she makes first and second degree," says Esther. "Unfortunately ... she has not graduated from secondary school. Not only that she's nowhere to be found."
A proud member of the choir in Chibok, she loved to sing, even while cooking, Esther says, breaking out into her daughter's favorite tune.
"I used to hear her sing [it] always," she says. "Anytime I want to recall her to my soul, I sing that song."
Esther Yakubu is furious at what she sees as a lack of action by successive Nigerian governments to secure the release of her daughter and the rest of the girls.
"The government has not done anything," she says. "When they attacked Chibok, the girls that escaped managed to escape themselves, by dropping ... down from the truck -- some girls even broke their legs.
"[They got] no aid from the government, no counseling. Nothing at all. Amina Ali that escaped [in May 2016], she managed to escape herself. It's unfair."
The Nigerian government has said it is still "in touch" with Boko Haram and "working for the girls' release," the Federal Ministry of Information and Culture said on its official Facebook page.
Esther Yabuku says the ongoing trauma of Maida's kidnap has had a lasting impact on her health: "My blood pressure has risen and it's not coming down."
At least 16 of the Chibok girls' parents have died while their daughters have been in captivity.
But the family says its unwavering Christian belief has kept it going through the darkest times.
They pray together every morning and every midnight that their daughter will make it home safely. The video, though disturbing, has given them fresh hope that Maida will soon be freed.
"I'm very, very happy," says Yakubu, having seen the video. "Because as long as she's alive, we will see her one day."