In reply to Bob Hughes:
Really sorry,
You might be overthinking (or over avoiding) this,
the NHS stuff is pretty vague information,
if you're really invested in seeing him do it, when you are well (but don't make vague excuses for not).
If you are self employed, just do it.
If not, explain to your employer and I'm sure you'll get compassionate leave.
Might be harsh, but speaking as someone that 'missed the boat'.
Regards,
Adrian
Post edited at 23:30