passport/registration for child of Uk citizen born in the US

[jh]

I haven't been able to get a clear answer or link on any situation although it doesn't seem complicated and must be common:
Our daughters were born in the USA (I'm married to an American - but born and grew up in the UK) and we would like to get British passports for them just to keep their options open as they get older. I can find that they are entitled to be British citizens by descent but no idea how to register them (with the home office somehow?) or to get their passports. Any help much appreciated.

[Jambo]

Consular birth registration is optional.

You can apply directly for a passport for them.

Your children will be British citizen by decent which means that they will not be able to transfer their British citizenship to their children (your grandchildren) if born outside the UK.

[jh]

Thanks for the response.
So we need to do a passport application for them and send their US birth certificates, my birth certificate from the Uk, and my "original british passport"? What does that even mean? I don't have my first passport from when I was a teenager? Can I send my current one?

[Jambo]

Original i.e. the passport itself, not a photocopy. Current passport is fine.

If your children were born before 2006 then a marriage certificate is also required.