Older siblings

So I'm now officially 6 weeks. I took my first hpt because my youngest out of the blue told me he wanted a baby sister. Sure enough next day took the test and bam positive. Well tonight while eating my youngest said he wanted a baby girl. Then my oldest said he wanted two babies, one boy and one girl! Has this happened to anyone else where the older suings were right. Also we have said nothing to our boys about the baby due to a miscarriage in 2010.