I know regular American citizens can't visit Cuba, but I have no idea if they make exceptions for those with family members.
How Long Can You Visit Cuba?
One needs to apply for Tourist Visa Card to visit Cuba and it's validity would be 30 days of stay within 180 days of issue. Further 30 day extension can also be availed. For more information, visit the link below.
www.directline-holidays.co.uk
www.directline-holidays.co.uk