Thanks for your question. I will try to help.
It’s going to be difficult for your partner. This is because you only have leave to remain on the basis that the father of your child has access rights to your UK child.
When your second child is born to your partner, that child will not initially have leave to remain. You will have to apply for leave to remain for this child.
Once the child has leave to remain then your partner must attempt to apply on a discretionary basis arguing that he should be allowed to have limited to leave to remain in the UK on the basis of your new child being in the UK and his relationship to you.
It’s a very specialised and complicated application. You will definitely need a solicitor practising immigration law to act on your child’s behalf and as on behalf of your partner when the time comes.
Provided that your child remains in the UK and your partner is the father of the child it’s going to be practically very difficult for the home office to deport your partner but this does not mean that getting him leave to remain will be simply.
You need to instruct a solicitor as soon as possible so that you can submit applications once the child is born,.
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