If a boy born on 14 April, 2009 then approximate date of conception is 22 July, 2008. This is approximate date because exact date of conception can not be calculated because ovulation can occur at mid of the cycle under normal conditions but it can also occur early or late. Egg after ovulation can live for 12-24 hours. Sperms can live alive for 3-5 days in female body after ejaculation. So, when ovulation and conception took place is assumed by considering normal conditions likes 28 days cycle and ovulation at mid of the cycle