Yes, you can use your child's CDA to pay for his/her sibling's cord blood banking service. Kindly provide the birth certificate of his/her sibling for verification.he CDA is a special savings account that you open at any OCBC Bank or Standard Chartered Bank branch for your child who is eligible for CDA. You can save in the CDA any time until 31 December in the year your child turns 6 years of age.