If the smallpox vaccine has not changed a lot in the meantime... Probability of death: 1 in 1 million. Probability of death for infants: 5 in 1 million.

Still not something to take a risk.

[Comparatively, if this source is not mistaken: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/safety/ad... for Covid vaccine 5 deaths per 1 million]