Parents should trust nature and time to reveal the handedness of their children and not encourage them to use either hand while still very young.
Here are the reasons why:
- The hand a child favors is genetically determined. When both parents are lefties, there's more than 50% chance their children will also be left-handed. When just one parent is left-handed, the chance of a left-handed child drops to about 17%. When neither parent is left-handed, it's down to 2%. Since it's nature, not nurture, at work here, encouraging your toddler to use his right hand won't help and could hurt.
- Handedness is not usually apparent until at least the age of 3, and some kids keep parents guessing for several years beyond that birthday. During these early years, it's common for children to appear ambidextrous, freely switching back and forth between hands until they decide which is the more facile. About 20% of children never settle exclusively on one hand or the other, but remain to some degree ambidextrous. Some ambidextrous children use both hands equally well and can employ either for almost any task: other switch off for for specific tasks - for example using the right hand for eating and the left hand for throwing.
- Research suggests that when parents try to "force" a child into using the hand he's not genetically programmed to use, handwriting and other problems can result. Consider, after all, how tough it is for you to try to write with the "wrong hand" just for fun; imagine how tough it would be if your were required to use that hand all the time.
Source: What to Expect the Toddler Years