Now my son very attached to pacifier. He cries when i took it especially when he bored or sleepy. So worry about it.. is it ok to let him use it for prolonged time?

perhaps not for a prolonged time, as it may increase the risk of ear infections, affect incoming teeth, and delay speech and social skills. a suggestion is to keep her mouth occupied, like getting her to speak or sing! that's what we did. i found this v helpful page for you on babies attachments to their pacifiers: http://www.whattoexpect.com/toddler/behavior/attachment-to-pacifier.aspx