"There is really no greater emissary than a family member when you're traveling abroad, because these are the people who are closest to the president," says Anita McBride, a former chief of staff to first lady Laura Bush. "They show something that is quite unique that no staff member, no adviser, no other emissary can really do."
According to the White House, Ivanka Trump's trip to Berlin, where she will attend the women-focused W20 Summit, was spurred by Merkel's participation in a roundtable the president's daughter hosted on Vocational Education and Workforce Development in Washington in March.
At the W20 summit, Ivanka Trump will take part in a high-profile panel on women's entrepreneurship that includes Merkel, IMF Director Christine Lagarde, Queen Maxima of the Netherlands, and Canadian Foreign Minister Chrystia Freeland, among others.
Trump will also visit the U.S. embassy for a meet-and-greet with embassy staff while in Berlin, in addition to visiting a technical academy and the Memorial to the Murdered Jews of Europe. She will cap her day by attending a gala dinner.
So, how unusual is it for a first daughter to represent the president abroad?
"It is not unusual that first family members would be engaged internationally with the full support of the president and the White House behind them," McBride said.
"We've had other first children represent their parents abroad. One of the best examples of that is Maureen Reagan, who traveled to Africa quite a bit on her father’s behalf," she continued. "She was very involved and very engaged."
And during her time working in President George W. Bush's administration, McBride said the 43rd president made it a priority to send a family member on a presidential delegation whenever possible.
"George Bush had traveled for his father to Zambia back in the 1990s and he saw first-hand how well received that was, as the son of the president, and he always remembered that," McBride said.
In the case of Ivanka Trump, McBride said, the first daughter has added credibility for this particular trip to the W20 Summit given her own experience as a woman entrepreneur and aide to the president on these issues.
"On a lot of levels, she's the right person to send," McBride said. "First, she's been personally invited by the chancellor. Two, she holds an official role and cares about these issues. And three, as the president's daughter, she's one of the closest people to him and he trusts her, and expects and wants her to be fully engaged on these issues for his administration."
Beyond participating in a panel discussion on women entrepreneurship, McBride said she's curious to see what deliverables the first daughter may have by the end of the trip.
"Is there something concrete? Is there something that she is going to point to that we are either doing or will be doing?" McBride said. "When you go to an event like this overseas, you are, as a general rule, bringing something to the table, so that will be interesting to see what she is offering."