Repairing a ‘pocket rip’

Very used to doing this, and it is worth googling ideas. I think your main decisions are:
Is the jacket to be relegated to 'messing about' - in which case a zig-zag, strengthened by tape is best.
Does he want to make it as good as possible, for show, in which case I would use a repair that sews up the pocket - a shame not to have a useful pocket - but could still look smart. Sewing by hand I would do a sort of darning / running stitch. Sometimes, if doing away with the pocket, you can use thread from the pocket to 'invisibly darn'.
Could you add a motif, contrasting tape or similar to make a feature - and jazz up other bits of the jacket so it looks intentional? There are loads of motifs on haby sites.
I have once, taken a contrasting piece of fabric and made 2 new 'patch pockets - but probably not if you're working by hand.
Hope that helps!

I’ve set up a website to teach clothes mending skills, which you probably all have and do anyway. But most don’t have the skills any more unless they have a lucky grandparent to teach them. Last night I had the second web call on tips for teaching mending in your community- if you are interested I could set up another. Email me on [email protected]? When it’s open again, does your community (school, church, cafe) provide an opportunity for you? The website and teaching is free, it’s my social legacy!