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Ha Mamathe, Lesotho — Senate Masupha sits in her family home in the village of Ha Mamathe in Lesotho, under a portrait of her late mother.

The inscription on the portrait, written in the Sesotho language, acknowledges her mother's role as principal chief of Ha Mamathe and the villages that surround it -- a position that she held for 12 years before her death in 2008.

Outside, the carefully tended flower garden, wooden trimmings on the porch and old sandstone buildings have a story to tell. For generations, members of the Masupha family have lived and served as chiefs of this area.

David Masupha, Senate Masupha's father, was principal chief before his death in 1996, and was a direct descendant of King Moshoeshoe I, the revered founder of Lesotho, home to the Basotho people.

"My parents were chiefs for all of their lives -- that was their right. I felt very secure when I was growing up," recalls Masupha. "But when my mother passed on, I was taken out of my comfort zone. There was a sudden tension in the family about who would inherit the chieftainship. I was a victim of this tension, because it was as if I wasn't even there."

Senate Masupha is fighting for the law on chieftainship to be changed.

Masupha is the only child in her family, but Lesotho's laws prohibit women from inheriting the chieftainship. Women can take on the role if their chief husbands die, but afterwards the position can be inherited only by a male heir.

When talk in the family turned to the possibility of evicting Masupha from her parents' home, she decided to take action. In 2013, she filed a case with Lesotho's Constitutional Court for her right to inherit the chieftainship, arguing that the existing law was discriminatory and therefore unconstitutional.

But the court rejected her case -- as did the Court of Appeal one year later, where the judge argued that modernizing the rule was a matter for Parliament.

Masupha's uncle -- her father's younger brother -- took over as principal chief, but she continues to live in her parents' home and to battle for change that she believes is long overdue.

Laws that prohibit women from inheriting the role of chief have been invalidated in South Africa -- and in Namibia, Botswana and Zambia, women can now be appointed chiefs on the same terms as their male counterparts.

Meanwhile, little has changed in Lesotho.

"A woman in Lesotho is not discriminated against -- she simply doesn't exist," says Kuena Thabane of the Lesotho Federation of Women Lawyers (FIDA), which has been supporting Masupha's fight.

Like Masupha, Kuena Thabane is frustrated by the current chieftainship law.

Sitting in her small, cluttered office in the capital Maseru, Thabane gives an exasperated half-laugh. "You can only discriminate against someone who exists, but in Lesotho's laws on succession and inheritance, women are not even mentioned -- they are entirely overlooked."

The Lesotho government has not responded to a request for comment.

Among Lesotho's 22 principal chiefs, who make up the majority of the country's Senate, Khoabane Theko, principal chief of Thaba Bosiu, says he is the lone supporter of Masupha's fight.

"A girl child does not choose to be born as a girl, so in my opinion the laws that discriminate against her are totally heinous," says Theko, speaking at his home near the historical mountain fortress where King Moshoeshoe I established the Basotho nation.

He points out the hypocrisy in the current system, in which female chiefs who take over from their husbands are generally well respected, yet their female children are denied access to the role.

"We don't consider the brilliance of a girl child and what she might be able to bring to the chieftainship if she was given the chance to rule," he says.

Khoabane Theko is one of Masupha's few supporters in the Senate.

Most other principal chiefs disagree. Peete Lesaoana Peete of Koeneng and Mapoteng holds firmly to prevailing cultural norms, arguing that in Basotho culture, a woman marries into the man's family and any future children belong to his clan.

"It cannot work the other way around," explains Peete. "If a girl child inherits the chieftainship she will take it out of the family when she gets married; she will derail the royal lineage. She cannot marry a man into her family. That is culturally taboo."

Thabane is frustrated by this view that privileges tradition above all else and believes culture should not always be preserved.

"In my opinion, culture is an instrument that is used to oppress, and especially to oppress women," she says.

Khoabane Theko, principal chief of Thaba Bosiu, reads the law against discrimination in the Constitution of Lesotho.

Masupha agrees, rejecting any logic that sees women getting married as an obstacle.

And she's hopeful that her constant campaigning, while having little effect on the laws of the land, is starting to have impacts at a grassroots level.

She begins to smile as she describes how some women in her community who are facing gender-based violence or discrimination often confide in her.

"This tells me that they understand my fight and that it's made them look at the reality within their own families and break the silence and speak out," Masupha says.

And it's a learning experience for her too. "Their experiences tell me that my case isn't only happening within my home -- it's also happening within my community."

Two residents of Ha Mamathe walk along a tar road leading to the village.

But raising Masupha's case with men and women at a bustling intersection in her home village reveals a divided community.

Mpoetsi 'Mamosa Lereka, 43, stands out from the crowd in her trousers and heels, a rare sight in rural Lesotho, where most women wear skirts or dresses.

Her face lights up when she hears Masupha's name. She remembers when her mother was chief and welcomes Masupha's challenge to the entrenched gender stereotypes that still govern the views of so many in Lesotho, including many women.

"When it comes to leadership, we always vote for men in Lesotho. We are made to believe that men should be leaders; that's our mentality," she says, adding: "We sideline ourselves as women. It's long overdue that this inheritance law changes; we need more women leaders in this country."

'Makhotso Makhoebe, a slightly older woman in a skirt, warm jacket and beanie, is one of those who opposes change. Shading her eyes from the harsh midday sun, she shakes her head as she speaks.

"Women should not be given leadership," she says. "They don't deserve that kind of power -- they have many more weaknesses than men and they don't know how to talk to people. We don't trust them. It's good that Senate Masupha lost her case."

A 70-year-old woman, who did not want to be identified, waits for a taxi on the outskirts of Ha Mamathe. She supports Masupha's fight. "Even if she was a girl, she had the right to be a chief," she says.

Inside the Masupha family home on the edge of Ha Mamathe, Senate Masupha reflects on her uphill battle.

"Patriarchy is entrenched in the fabric of our society, to the extent that women themselves see it as a normal way of life and continue to enforce it," she says, a hint of tiredness in her voice.

She sighs, shifts in her seat and then raises her head, her expression still determined as she points out the progress toward gender equality made by Lesotho's neighbors.

"There's no way that Lesotho can sustain its current retrogressive laws," she says. "It's only a matter of time before we get to where we're supposed to be."