The foundation supported study looking at the safety of ibuprofen in children younger than six months of age finally completed. Over 12 million rows of data and years of weekends and evenings preparing data finally revealed a more nuanced answer than a simple yes or no.  The short version is that ibuprofen is not inherently less safe in children younger rather than older than six months. However, using ibuprofen is associated with more (albeit mostly mild) adverse GI events. The risk ratios should be tempered by absolute risks which were very low.  The paper is here