Before Anna was born, we took family bike rides in the following way: Margaret and I rode our own bikes, and Tony pulled a two-seater trailer with the little girls on board. We've been struggling lately with the dilemma of how we can bring everyone along now that we have one more kid. We considered getting Sophie her own bicycle so that Anna could take her place in the trailer, but she doesn't ride without training wheels yet and she's really too little to keep up. Then Tony had a great idea, and we purchased this tandem bike attachment:
Isn't she cute? She's really happy, too. So now our family bike rides will go thus: Tony with Sophia on the tandem bike, Me pulling the trailer with the two little ones, and Margaret riding her own bike (lucky).
I think riding the tandem bike will help Sophie learn to balance as well, I guess we'll see.