Congratulations. I’m sure you’ll be fine. You aren’t a first time mum and have all that experience to draw on.
I’m an older single mum too and it is hard work. I found it helped to try to improve my fitness because then I had more energy and less sick time.
As for the ex, don’t add him to the bc, let him apply if he wants to. Get childcare and routines in place and be guided by how he acts. Try to keep it amicable so your son has a good relationship with his dad but don’t rely on him if you can avoid it. If you are really worried, make sure you know what the law is around shared custody, and how to deal with any problems. Good luck x
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