Wenger has been talking with Lemar's dad for a number of weeks now apparently. I think that's Wenger's way. He likes to meet the family and put the personal touch on deals
With Mbappe he has supposedly spent a lot of time talking with the family too. I think he recognises that particularly with the younger players it's important for the family to feel happy and confident in the manager of a new club.
Wenger's name holds a lot of respect, especially in France. Most of these youngsters have grown up seeing and looking up to Arsenal teams managed by Wenger. They've seen him produce some great football and made young French players superstars. Lacazette is probably thinking about all those magical nights that Henry produced for us and wants to do the same. Let's all hope he does the same.

I know Wenger has his flaws, but give the man some credit when he actually changes something for the better. God knows we've been slating him for being too stubborn, then when he does change and makes an improvement, some people (Yes you Cini) are still slating him.
