First lady Michelle Obama has said she hopes to inspire young adults during her visit this week to South Africa and Botswana, but she seemed inspired herself after a brief visit Tuesday with former South African president Nelson Mandela.

The unscheduled talk with Mandela, the nation’s first black president and patriarch of racial equality here, came after a visit to his foundation. Mandela, 92, who has not been seen often in recent months, is revered here. He was hospitalized in January, and rumors of his ill health have been reported in the local news media.

In photos taken of the private 20-minute visit between members of Mandela’s extended family and Obama, her mother, daughters, niece and nephew, he is sitting on his couch holding a book of his quotations that he is signing for the first lady.

Earlier, during a tabletop tour of a display of letters, photos and years of desk calendars that Mandela kept while in prison for 27 years, Obama said, “Wow,” and asked how he kept up with all of the documents.

This is her second solo official visit and her first time in South Africa. Her schedule is packed, including a visit to the jail cell where Mandela was held on Robben Island and to a medical clinic in Gaborone, Botswana. She is also scheduled to give a keynote speech at a church in Soweto that served as a hub for the movement against apartheid — South Africa’s system of racial subjugation.

Obama will stop in four cities in six days, with her travels intended to focus attention on two successful African democracies and to highlight programs addressing concerns such as the high rate of HIV infection here.

After a quiet arrival late Monday following Father’s Day celebrations with President Obama, she awoke early for the day of meetings with South African dignitaries and historical remembrances of the nation’s racial struggles.

The events are an attempt to adapt the mentoring and wellness programs that the first lady has honed in the United States to an international audience while engaging in official business. Obama’s visit to Mexico, her first solo official trip, and to Britain and India with the president, have had similar themes.

She began the day, without her mother and the children, at private meetings at the U.S. Embassy compound in Pretoria and a visit with Nompumelelo Ntuli-Zuma, one of the three wives of South African President Jacob Zuma, at the presidential mansion in in that city. Zuma, a Zulu traditionalist who has been criticized by advocates of women’s rights here, was not present.

Obama spent more time and appeared relaxed with Graca Machel, Mandela’s wife and the former first lady of Mozambique. Machel took Obama’s arm as she and her family toured her through the archives with the foundation’s staff.

When Machel lost sight of Obama’s mother Marian Robinson, she called out, “Are you there, Ma?” Robinson smiled and pulled in closer.

About two dozen South Africans lined the streets around Mandela’s home, shouting “Welcome to South Africa” as Obama’s motorcade passed through, but there were no big crowds. Later, Obama and her family toured the city’s renowned Apartheid Museum in a private tour.

Obama has made clear that her focus will be on children, and she energetically tickled and hugged the elementary-school-age youngsters she met at Emthonjeni Community Center in Zandspruit, a sprawling shantytown of homes — many without electricity and plumbing.

Accompanied by Robinson, her daughters Sasha, 10, and Malia, 12, and niece Leslie Robinson, 14, and nephew Avery, 19, Obama sang songs and played a game in which she wobbled her knees along with the youngsters, who said they were showing their “happy.”

“I like happiness,” she said as she danced along.

Obama donated 200 books to the center, aides said, and she and her daughters read “Cat in the Hat” by Dr. Seuss. Malia and Sasha, who are rarely seen publicly in the United States, read their parts with verve.

The Emthonjeni center was chosen as a stop by State Department officials because founders of an affiliated nonprofit group participated in a forum President Obama held last year at the White House focused on young African leaders.

Several young women who attended that forum have been invited to meet with Michelle Obama on Wednesday, where she will give a keynote speech on the importance of leadership among young adults.