Question

Ann-marie started walking when she was 10 months old; cynthia is just beginning to take steps by herself at 13 months. Which conclusion is most likely true? _

Answer 1

I believe the answer is: Both girls are developing normally.

What considered to be normal for children to take their first step if it's happen when they are around 9 - 17 months old.  The stagnation could be explained because different children need different time for their skeletal and muscle to be developed.

Answer 2

Ann-Marie started walking when she was 10 months old; Cynthia is just beginning to take steps by herself at 13 months. Both girls are developing normally.