No, not everyone in your family needs to have a Social Security number (SSN) to qualify for the Child Tax Credit. According to the IRS FAQ, to claim the Child Tax Credit, you and your spouse (if filing a joint return) must have either a Social Security number (SSN) or an IRS Individual Taxpayer Identification Number (ITIN) issued on or before the due date of your tax return. However, each qualifying child you claim for the Child Tax Credit must have an SSN that is valid for employment and issued by the Social Security Administration before the due date of your tax return.
Therefore, while you and your spouse can use either an SSN or ITIN, each qualifying child must have an SSN to be eligible for the Child Tax Credit.
Sources:
Publication 3 (2023)
§ 24. Child tax credit
Publication 501 (2023)
