Does this sound weird to anyone else?

My parents divorced when I was 2 (I'm 14 now) and they both remarried. Well, about a moth ago, my mother and step-father told me that they are going to have triplets. I'm excited because I'm an only child and always wanted a brother or sister. Well anyway. Yesterday my Dad and step mother told me that they are pregnant with TWINS! They're (My mom and stepmom) due dates are 3 weeks apart. Of course I'm excited... but I think its kinda weird that both of them are having multiples. SOOO does anyone else think that this sounds a little strange?