Here in San Francisco? On my insured Stromers, with my family, that I bought for less than the cost of a year of auto insurance. Door to door, I am everywhere I want to be in about 10m. My longest typical journey is 45m across Golden Gate Bridge from the Mission, which is faster than any car, simply because I park my bike at the door of my destinations.
The better question is, have you ever seen a kid crying in the back of a bike?
Everyone I know who bikes in the city has been hit by a car at some point (see: my complaints about enforcement of traffic laws in this thread if you want my opinion on that).
I cringe when I see parents with their kids on the back of their bikes. Super dangerous.
The better question is, have you ever seen a kid crying in the back of a bike?