She doesn't want parents to leave central american countries in order to go to America because it encourages children to leave for the US and disrupts families.
Additionally, children should not make the journey to the US because it is very dangerous and will continue this cycle.
This is largely a thematic question. Abandonment of family is at the heart of this issue. At various points of the book, Enrique is abandoned by every significant parental figure in his life. First, Lourdes emigrates to the United States, leaving a five year old Enrique to be raised by his irresponsible father. Then, his father leaves to begin a new family, after which he is traded from home to home, largely because of the rebellious attitude that forms in response to the abandonment. In many ways, it is adolescent confusion over this abandonment that inspires Enrique to brave the significant risks of the journey to reunite with a mother he barely knows. Though this pain does inspire Enrique to fear repeating the cycle, he does abandon María Isabel, his girlfriend, who is pregnant with their child. The theme of abandonment comes full circle when Enrique and María Isabel leave their daughter in Honduras while they create a new life together in the United States. Enrique's greatest hope is that he can bring his daughter to him and not prove guilty of the same offenses that corrupted him in his youth. You can explore more themes at the GradeSaver link below:
http://www.gradesaver.com/enriques-journey/study-guide/themes
