As you have a young kid in the house, I think it is a MUST for you to take the necessary precaution.
For HDB flats, you have 2 choices. Install proper aluminum grilles. Or install invisible grilles.
For condos, you might want to check with your MCST on the approved grille designs you can install. Alternatively, invisible grilles are largely approved as they do not greatly affect the facet of the building.
Should you need any further assistance in matters relating to property, please contact me at my mobile 9748 6305. I will be happy to assess and share with you the possibilities for you and your partner in the current market.