title: The growth and development of six XYY children.
mesh_terms: D002170:Canada; D002648:Child; D002675:Child, Preschool; D005500:Follow-Up Studies; D005817:Genetic Counseling; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008607:Intellectual Disability / Q000235:genetics; D008297:Male; D010553:Personality Development; D010641:Phenotype; D012729:Sex Chromosome Aberrations / Q000523:psychology*; D014997:XYY Karyotype / Q000523:psychology*