I treated my son to new trail running trainers yesterday as an encouragement to keep him running with me on Sundays. I really enjoy his company, even if he is reluctant. I'm sure he does it for gaming time really.
I too changed my trainers, for an older pair from the back of the cupboard, and was surprised at the difference they made. A lot less hip discomfort...perhaps a bit more arch support...so maybe I'll try them again on next week's run. Week 5 here I come!
Sounds like its going really well. I'm a week behind you now (painful blister) but starting week 4 tomorrow all being well. Good luck with week 5, that's my 'treat myself to new trainers' week if i complete it 
What an inspiration you are to your son.... showing him how it's done and cleverly keeping him on track! Even if you think he's not interested, the fact that you are out there doing it, will be impressing him (on the quiet maybe!).
I like the way he get the new trainers and you make do with the old pair, only a mother would do that! Trainers are really important and if they aren't right can lead to injury so if your hip feels better with your 'new' old pair I'd stick with them.
You are doing great, good luck with week 5. You can do it
W4r3 - want to stop now please
Shoes!!! 
Advise needed on running shoes
Shoes
