Any way to gently handle this neighbor problem?

[Nitrousbird]

My Jimmy is parked closest to their house.

 

I've been letting the car roll out into the street before I fire it up (as sometimes I don't remember to park it in the street/no spots because a bunch of people are over). They haven't said anything to me yet. He said they never hear it start or me leave, just the baby wakes up.

 

So I dunno if the kid is still waking up or not; I'll ask next time I see them. The car is in the culdasac now running for 10 seconds total; start it in the street, and pull off very gently at 1500 rpm or less....not loud at all. I listened to my roomate roar the car out of the driveway yesterday afternoon, and it wasn't loud enough to wake me up if I was sleeping, and that was in my own house in my driveway.....but I can sleep through normal noises too.