Is my relative entitled to Personal Independence Payment (PIP) mobility allowance?

I looked this up and it's a UK thing correct. Hopefully someone from the UK can help. At this forum we r from the US, Canada and the UK. We talk about our Caregiving hoping to help each other. Here is a site I found.

ageuk.org.uk/information-advice/money-legal/benefits-entitlements/personal-independence-payment/