Garrett rides a bike...almost!

Paul and I feel like we have conquered many milestones with our children. Getting them to take a bottle, taking away the bottle, sleeping through the night, potty training, going to nursery or school, etc. One of these milestones we have recently been working on is riding a bike "a two-wheeler" (as Garrett calls it). We want so badly for him to figure this out, he actually has little interest in this activity, but we keep telling him he will love riding his two wheeler once he's caught one. So we have promised him a big deck (not just a pack) of pokemon cards once this milestone has been accomplished. If any of you have been around Garrett for too long, you know he is very motivated by Pokemon, so we are now in business! Gaarrett is getting so close. But we need so help, does anyone have any pointers on how to help someone catch on to riding a bike?