well, i think it all depends on individual. most ppl tell me 1-2 yrs age gap is the best so they will be closer and many things can be pass down. But for me, i prefer my kids to have 3-4 yrs age gap. cos by the time dear son is 3yo, he might understand more when we tell him more on the coming sibling. i have a friend whose 2 kids age gap is 4yrs, and the elder bro dote on the lil bro alot and can even play together. and i prefer to take care my kids on my own, so if the age gap is too near, might be abit tiring. haha..