How do I go about doing a deed poll if my child is not born is Singapore?

Am I right to say that your child is a Singaporean but not born in Singapore? If that is the case, you should be able to engage a lawyer in Singapore for a deed poll. A Deed Poll can be signed in Singapore by a Singapore Citizen or a foreigner who is a Singapore Permanent Resident. A minor (person less than 21 years of age) requires either of his/her parents (i.e. father/mother) to sign the Deed Poll on his/her behalf. A Deed Poll is required for changing the name in the Identity Card at the Immigration and Checkpoints Authority (ICA) in Singapore. An adult changing the name of his/her minor child older than 1 year, can only change the name in the Identity Card of the minor child and not the Birth Certificate of the child. http://www.myfamilylawyer.com.sg/html/name_change.html