HELP! Separation Anxiety

I'm looking forward to my baby girl being born but I'm not looking forward to be separated from my son. By the time of my baby girl's expected birth my boy will be almost 13months old & I've only been separated for 24hrs from him at 3 different times & I can't even make it those 24hrs without having a mental breakdown & crying. With me having an induction & being GBS positive again I'll be separated from my boy for a minimum of 3 days. Anyone have any tips on helping with separation anxiety?