baby's backbones not fully developed, cannot let them start to sit too early, so not even to sit on walker la......... will hurt the bones ga.
at least wait till bb can sit first, before letting them to use walker
學行車 no good, try not to use...
1) baby don't like walking by themselves anymore because 學行車 is way faster and use no strength
2) bad for hip bones
3) dangerous issue such as rolling downstairs