Actually, despite what I said I here I ended up getting DS a bike. He was just too tall for the balance bike, and kept asking me to raise the seat, and if I raised it anymore he would fall off!!
He is doing fab
, but we do have stabilisers on for now. But he rode 2km on a local cycle path today and was just fine.
Megan has just started on the balance bike and is walking nicely with it. Hopefully she will start to run soon!
I will still pop DS on the balance bike as well and try and take the stabilisers off very soon.