Buddy Bike for Madison

Madison loves to be outside and riding bikes. However, she is unable to ride a “regular” bicycle. She has balance issues and is unable to stay upright on her own bike. I have tried rigging the back of my bike with a trail gator and different types of seats, but they never seem to quite fit or hold her well. It is difficult to ride a bike with Madison behind me because I can’t see how she is leaning so I am always trying to compensate for her and struggling to keep both of our bikes upright. Therefore, she ends up in the bike trailer often. 
She is getting too tall for the trailer and her head is popping up through the material and the bottom of the carrier is starting to rip at the seams.
I know having a Buddy Bike will open up a whole new world for her. Her therapists state that having a Buddy Bike will encourage Madison to gain more physical strength/stamina because she will be peddling in front of me and will be upright at all times.
A buddy bike will allow for family quality time and ultimately, Madison's continued love of being outside and riding a bike that will make her feel independent and confident!