If you are a permanent resident in the UK and currently living here or if you are a British citizen, you can apply for permission for your children under age 18 and dependent relatives to travel to the UK in view to settle with you on a permanent basis (settlement visa).

Once in the UK, they will be able apply for permission to settle permanently (indefinite leave to remain).

All about Settlement visas and Indefinite Leave to remain (ILR)

If you have legal status in the UK or are a British citizen and are in a stable relationship with someone from outside the EEA (visa national) and you want your partner to come and live with you here on a permanent basis, whether you are married or not, or whether your relationship is opposite or same-sex, your partner may be eligible to apply for a settlement visa.

Once settlement visa is granted, after passing a probationary period of 2-years together in the UK, permanent settlement, i.e. indefinite leave to remain (ILR), can by applied for.

Documents to submit when applying for settlement.

How to enter the UK to join with your Fiancé(e)s or Proposed civil partner