In reply to Tree.
The grant is only eligible for Singaporeans, so whether your wife is a PR or not, the grant amount you can get will be the same. But you may be able to get a S$10,000 Citizen Top-Up Grant if someone in the family (your wife or child) gets Singapore citizenship. You can read more about it here https://www.hdb.gov.sg/cs/infoweb/residential/servicing-your-hdb-housing-loan/citizen-topup