my son is 4 years old and since yesterday he has not left my side like he knows something is going to happen. he hugs me…

my son is 4 years old and since yesterday he has not left my side like he knows something is going to happen. he hugs me and tells me i love you mommy and says stuff about his baby sister. then my daughter who's 6 tells me she's been having dreams about me having her baby sister soon. this makes me nervous.