telling your child he/she is going to have a baby brother/sister

How did your child react. My son is 3 1/2 and has been saying for months that he wants a baby thought you could buy a baby from walmart and cried when I told him we couldn't lol. I am almost 11 weeks and we told him yesterday he thought I was being silly 😅 I told him that mommy had a baby in her tummy and he pulls up my shirt and said let me seee!!! he's so cute glad he didn't freak out now today he keeps asking for a baby sister he's such a sweetheart I can't wait !!