DD1 would not stay in her stroller. I gave up one day after she literally started headbutting the footpath (it was one of the lightweight, low-to the-ground strollers) and trying to get out. From then on I had to let her walk with a harness (she was a bolter and would not hold hands). Same with high chairs.

DD2 is also showing signs of the same. I gave up on the highchair a couple of months ago as every meal was impossible, I'd constantly be trying to get her into her highchair and restrap her. I now set the girls up at their 'little table' with little chairs or let DD2 kneel on a normal chair at the dining chair.