The Asahi Article mentioned that the crown prince family will stay with Queen Beatrix during their stay in the Netherlands.....so I guess Aiko will have a chance to meet with Amalia and Alexia
Crown princess to recuperate abroad
06/24/2006
THE ASAHI SHIMBUN
After two years mostly out of the public eye due to stress-related illness, Crown Princess Masako is to travel to the Netherlands to recuperate. Issei Nomura, grand master of the Crown Prince's Palace, told a regular news conference that the princess, along with her husband, Crown Prince Naruhito, and the couple's 4-year-old daughter, Aiko, will stay with Queen Beatrix.................
http://www.asahi.com/english/Herald-asahi/TKY200606240142.html
Japan's stressed princess to rejuvenate in Netherlands
TOKYO (AFP) - Japanese Crown Princess Masako, who has been ill with stress while adjusting to life within the world's oldest monarchy, will go abroad with her family for the first time to take a holiday in The Netherlands, the palace said.
Masako, her husband Crown Prince Naruhito and their daughter, four-year-old Princess Aiko, will vacation from mid to late August in The Netherlands, where her father is a judge on the world court.
It is the first known time that a Japanese royal has gone abroad for recuperation purposes. Masako last went abroad in 1999 for a royal wedding in Belgium.
Masako's doctors had recommended the trip, which came at the invitation of Queen Beatrix, as "to rest in a quiet environment overseas and spend time with family would benefit her health," an imperial agency official said............................
http://news.yahoo.com/s/afp/20060623/en_afp/japannetherlandsroyal_060623171732
photo from AFP of her recent appearance