Have your FSH tested if you're concerned with lowered fertility. My siblings and I are far apart in age and we have a close relationship. I don't think that has anything to do with age spacing but how much you're willing to work on the relationship. If you're trying to help build a house it's not a great idea to be pregnant and postpartum. FYI the rate of developmental complications goes from 0.5% to 1% when you get to 40. It's not that big of a difference.
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