When the Chinese and US presidents met on Monday, their talks included not only world and bilateral issues, but also something about the family.
President Xi Jinping mentioned Barack Obama's wife and daughters by their first names and the US leader's mother-in-law by her surname to show respect.
"Before arriving in the Netherlands, my wife and I met and had pleasant talks with your wife Michelle, your mother-in-law Ms Robinson and daughters Malia and Sasha.
"They are visiting China, and I believe theirs is a friendly and unforgettable trip," Xi told Obama in The Hague, hours before the start of a nuclear summit.
Xi even joked that when their meeting ended in Beijing last week, Michelle Obama had asked him to "formally convey her best regards"to Obama.
But Xi knows even better how to steer relations between the world's two largest economies along the right track.
"China is willing to work with the United States to keep the two nations on the right path toward building a new type of major-country relations," he told Obama.
The Chinese leader said he appreciated a similar commitment from the US in a letter he received recently from Obama.
Xi added that he agreed with Obama's comments in the letter that China-US cooperation is beneficial for the two countries to promote shared interests and to deal with common challenges.
Beijing will remain committed to the policies of non-confrontational actions, mutual respect and win-win cooperation, Xi said.
Obama thanked Xi and his wife "for being such a gracious host to Michelle for her first visit to China". The US first lady arrived in Beijing on Thursday for a weeklong tour of the country.
Obama also joked that "she also played some table tennis, although I think this was not the high level ping pong diplomacy that we saw in the past."
The US president said the two countries not only work on issues of mutual interest and concern, but are also able to work through frictions that exist in their relations such as human rights, or dealing with maritime issues in the South China Sea and the Pacific region in a way that is constructive and hopefully will lead to solutions for all parties.
Obama added that he believes ultimately that by working together, China and the US can help to strengthen international law and respect for the sovereignty of nations.
Experts said that frequent meetings between Chinese and US leaders at bilateral and multilateral gatherings are conducive to achieving common goals within the framework of a "new type of major-country relationship".
"The US has responded vaguely to the concept that China proposed last year, so the two countries need to take every opportunity to communicate, dispel misunderstanding and expand the concept's connotations," said Su Hao, a professor of Asia-Pacific studies at China Foreign Affairs University.
Teng Jianqun, a researcher of US studies at the China Institute of International Studies, said Sino-US relations have been upgraded in many aspects, including politically and militarily, since June when Xi and Obama met in California.
"Leaders of the two countries have established positive working and personal ties, especially considering US first lady Michelle Obama is currently touring China," Teng said.
Analysts also said austere situations regionally and internationally call for more interaction and consultation between Beijing and Washington.
"China has moved toward the centre of the international arena with significantly improved national power over recent years, but the country has not yet been able to assume the role as a real world leader," Teng said.
"China and the US will have to cooperate in order to address many global issues, such as anti-terrorism and nuclear non-proliferation," he added.
Su said that escalating tensions in Ukraine and the Middle East have left Washington in a very awkward position. "The US would welcome China playing a more constructive role on these issues."
Apart from Obama, Xi is scheduled to meet French President Francois Hollande and German Chancellor Angela Merkel on his four-country European trip, which started on Saturday and ends in Belgium on April 1.