B.C.
Our son was 25 lbs on his first birthday.
He walked at 14 months.
He just needed to be a little bit stronger to handle his weight.
Then he went from toddling straight to running.
By 2 1/2 he was too fast for me to catch him.
I had to have him on a leash for a year when we went out so he wouldn't dash away on impulse.
He doesn't need any weighted push toys.
Just let him cruise and stand - it all builds muscles - and before you know it he'll be running and climbing all over the place!