Applicants/Sponsors with a large difference in ages The rules do not state that the applicant and sponsor must be within a certain age differential, but if there is a disproportionate age difference (for example, more than 25 - 30 years), additional care needs to be taken. If the sponsor (applicant) has grandchildren that are older than the applicant (sponsor), the application can be tenably refused on credibility grounds. In these cases, professional advice should be sought prior to submitting the application.