http://www.telegraph.co.uk/education/educationnews/11787848/Bilingual-children-lag-behind-in-English-research-shows.html http://www.telegraph.co.uk/education/ed

http://www.telegraph.co.uk/education/educationnews/11787848/Bilingual-children-lag-behind-in-English-research-shows.html http://www.telegraph.co.uk/education/educationnews/11787848/... Bad paper summary of an study but I think there's been a few studies