I think it really depends on your own situation and really you can make the best of any age gap that you have...having said that...my brother and I are 14 months apart and it was horrible..we really hated each other until our late teens!
My eldest dd and her sister are 26 months apart and I found that to be really good. Jess was out of nappies during the day and she was able to have some understanding of a little baby and it worked well with big girl versus baby. Emily and Olivia are 21/2 years apart and I loved that even more. Em was that little bit older again and more able to understand what was going on. As sisters the girls are all very close now and really do get on well. We have 63/4 gap with Olivia and Sammy...and it really feels like my first all over again...cept I have some great little entertainers and they arent in the least bit jealous of him. Thats probably what I have noticed most this time around that the sibling rivalry is virtually non existant with such a big gap.
Have fun in deciding what is best for you and your family. I really do think you can make the most out of any situation.
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