Tax- applying for single parent extra half part (household)

I’m going to apply for an extra half part on my tax return. It seems as I was a single parent in the UK bringing up my first daughter (5 years I think is the minimum) I can request a lifetime half part.

I wonder if anyone has done that, (seems plenty of single parents on the site, but nothing about the 1.5 parts) and what evidence etc…

A lady French friend has this (80yo) and did an attestation sur honour only, suspects applying might not be so smooth as a male person and UK documents such as custody award etc will need translating. And at 35 years ago when my daughter was born, there aren’t so many either.

Asked the tax inspector about this, he said, yes you will qualify after I explained the background, try to get as many documents as you can, but there is appreciation that sometimes it is difficult after some years have passed…

Any advice / stories gratefully received, thanks.

Have a search to see if there is an SOS Papa regional group in your area. They could well have much experience to share.