Hand preference is determined by genetics

Generally, most people are right handed. When a child uses one hand more consistently than the other hand and is more skilled at tasks when using that hand, this is considered to be the dominant hand. This is also referred to as hand preference.

Your child's preference for the right or left hand may start to appear as early as six to nine months of age but you won't be able to determine true right or left-handedness until your child is two or three years old. Hand dominance is greatly influenced by genetics. If both you and your partner are left-handed, your child has a 45 to 50 per cent chance of being left-handed as well.