( CNN ) -- First lady Michelle Obama met with former South African President Nelson Mandela on Tuesday as part of a weeklong visit to the continent , according to a spokeswoman for the first lady . Accompanying her on her visit with Mandela were a nephew , Avery Robinson , 19 , and a niece , Leslie Robinson , 15 , children of Obama 's brother , Craig Robinson , according to Semonti Stephens , deputy communications director for the first lady . Obama also was expected to visit other luminaries in the country Tuesday after arriving in Pretoria Monday night . The first lady 's trip highlights the value of South Africa as a viable partner with the United States in issues other than politics , said John Campbell , who holds the Ralph Bunche chair in African Policy Studies at the Council on Foreign Relations . `` What is significant about the trip is that it underscores the fact that South Africa , since the establishment of nonracial ( politics ) has had a string of credible elections , is a country characterized by the rule of law , and is a democracy , '' Campbell said . `` Twenty-five years ago I think relatively few of us would have predicted such a happy outcome . '' Obama is scheduled to visit several historical sites , including Robben Island , where Mandela was held for much of his 27-year imprisonment in his fight against apartheid . Obama , traveling on what officials have said is her second solo official visit to the continent , has brought her daughters , Sasha and Malia , and her mother in addition to her niece and a nephew . `` One of the things bringing them along demonstrates is the closeness of the Obama family , '' Campbell said . `` And this is something that the people of Africa respond very well to . Certainly before her , Laura Bush made a number of trips to Africa as well and was very well received . '' The visit will further raise the profile on the continent of the first lady and the president , whom many Africans regard as a favorite son . `` The Obamas as a couple are extremely popular in Africa and obviously 100 % well-known there , '' Steve Howard , director of African studies at Ohio University , said Tuesday . `` Her husband ca n't spend that much time there so they are dividing the labor , and she is representing them in South Africa , which is a major media market as well . '' Howard said Michelle Obama 's visit especially will resonate with the nation 's youth . `` It has an enormous young population , probably more than 60 % of the population is under 18 , '' Howard said , `` and they have a lot of health-related issues , particularly AIDS , and so everything she does there will help bring attention to global health issues . '' She is also expected to visit Nobel laureate Archbishop Desmond Tutu as well as Soweto , just outside Johannesburg . In addition to visits with top leaders , Obama will be a distinguished guest at several public events , meet embassy officials and take part in community service projects in both South Africa and Botswana . `` The trip is a continuation of Mrs. Obama 's work to engage young people , especially girls and young women , at home and abroad , '' the White House said . Her visit to neighboring Botswana on Friday will include attending a tribute to girls overcoming obstacles as well as a luncheon with women leaders . She will also meet with President Ian Khama before retreating to a local game reserve for the weekend . After a safari , she is scheduled to depart from the Botswana capital of Gaborone on Sunday . Journalist Craig Johnson contributed to this report .
Obama : The South African trip establishes the nation as viable partner , expert says . The visit will further the profile of the Obamas on the continent . The first lady and president are scheduled to be in Botswana Friday .